diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index de44884898256ff7f2de65400dabada858e7cc4c..02e28fa0e716ff807759b7b2452c51db8bc850bc 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -2,7 +2,7 @@ variables:
   TESTV_DIR: "/usr/local/testv"
   LTV_DIR: "/usr/local/ltv"
   EVS_BE_TEST_DIR_BASOP: "/usr/local/be_2_evs_basop"
-  REFERENCE_TAG: "20231128_Update_Ittiam"
+  REFERENCE_BRANCH: "ivas-float-update"
   BUILD_OUTPUT: "build_output.txt"
   SCRIPTS_DIR: "/usr/local/scripts"
   EXIT_CODE_NON_BE: 123
@@ -92,7 +92,8 @@ stages:
 .setup-codec: &setup-codec
   - current_commit_sha=$(git rev-parse HEAD)
   ### build reference binaries
-  - git checkout $REFERENCE_TAG
+  - git checkout $REFERENCE_BRANCH
+  - git pull
   - make clean
   - make -j
   - mv ./IVAS_cod ./IVAS_cod_ref
diff --git a/lib_com/ivas_cnst.h b/lib_com/ivas_cnst.h
index 2e36dc4693b011a6ad2a49646143033cf40c2b66..dae981352862bdd34dfbb55e26fdce08ef018807 100644
--- a/lib_com/ivas_cnst.h
+++ b/lib_com/ivas_cnst.h
@@ -1187,6 +1187,10 @@ enum
 #define MASA_MAXIMUM_DIRECTIONS                 2
 #define MASA_MAX_TRANSPORT_CHANNELS             2
 
+#ifdef  NON_BE_FIX_1048_THRESHOLD_COH_BASOP
+#define MASA_SUR_COH_THRESHOLD                  1e-7f
+#define MASA_SUR_COH_PRECISION                  1e7f
+#endif
 
 #define MASA_NUM_DEFINED_SUR_SPR_COH_ENE_BINS   5
 
diff --git a/lib_com/mslvq_com.c b/lib_com/mslvq_com.c
index 39a1c4c69927c2f27108a11532227b573a4ab68a..77fb370a729bef1d0c1f37be36d28dfa9bb72364 100644
--- a/lib_com/mslvq_com.c
+++ b/lib_com/mslvq_com.c
@@ -919,7 +919,11 @@ void deindex_lvq_SHB(
 
         /* find idx_leader */
         i = 1;
+#ifdef NONBE_FIX_1054_NEGATIVE_LVQ_INDEX
+        while ( index > table_no_cv[i] )
+#else
         while ( index >= table_no_cv[i] )
+#endif
         {
             i++;
         }
diff --git a/lib_com/options.h b/lib_com/options.h
index ab10c15b7d934cf49c5445f866171fbdfec49052..366354dc890d594c3814771366c0b9b3bc016745 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -68,6 +68,12 @@
 
 /* #################### End DEBUGGING switches ############################ */
 
+/* ################### Start FIXES switches ########################### */
+
+#define NON_BE_FIX_1048_THRESHOLD_COH_BASOP             /* Nokia: Fix 1048 replace comparison with 0 with comparison to threshold, to align with BASOP*/
+#define NONBE_FIX_1054_NEGATIVE_LVQ_INDEX               /* Nokia: issue 1054: Input to decode_comb in deindex_lvq_SHB should be positive */
+
+/* #################### End FIXES switches ############################ */
 
 #define BASOP_NOGLOB                                    /* Disable global symbols in BASOPs, Overflow/Carry in BASOPs disabled, additional BASOPs in case of Overflow */
 
@@ -94,6 +100,7 @@
 #define BE_FIX_832_ASAN_ERROR_EFAP_OSBA                       /* FhG: issue #832: fix ASAN error caused by re-allocating EFAP memories in OSBA*/
 #define NONBE_FIX_819_DOUBLE_PREC_COMB_FORMATS                /* VA: issue 820: Double precision arithmetic in combined formats */
 #define NONBE_FIX_849_OMASA_BFI_CRASH                         /* VA: issue 849: fix OMASA 2TC and FEC crashes */
+#define NONBE_FIX_738_QUATERNION_SLERP_PRECISION              /* Quaternion slerp changes*/
 #define IVAS_FLOAT_FIXED
 #define ISM_DISABLE
 #define FIX_TMP_714
diff --git a/lib_dec/ivas_qmetadata_dec.c b/lib_dec/ivas_qmetadata_dec.c
index 369ca37b067432f88dac662bf686a35d16f0ba62..9242d0672747e08a387d203893032a54c41723c9 100644
--- a/lib_dec/ivas_qmetadata_dec.c
+++ b/lib_dec/ivas_qmetadata_dec.c
@@ -7940,6 +7940,9 @@ static int16_t read_surround_coherence_hr(
     IVAS_QDIRECTION *q_direction;
     int16_t min_index;
     int16_t d, idx;
+#ifdef NON_BE_FIX_1048_THRESHOLD_COH_BASOP
+    int32_t int_error_ratio_surr;
+#endif
     coding_subbands = hQMetaData->q_direction[0].cfg.nbands;
     q_direction = hQMetaData->q_direction;
 
@@ -7963,6 +7966,11 @@ static int16_t read_surround_coherence_hr(
                 error_ratio_surr = 1.0f - q_direction[0].band_data[j].energy_ratio[sf];
             }
 
+#ifdef NON_BE_FIX_1048_THRESHOLD_COH_BASOP
+            int_error_ratio_surr = (int32_t)(MASA_SUR_COH_PRECISION * error_ratio_surr);
+            error_ratio_surr = (float)(int_error_ratio_surr * MASA_SUR_COH_THRESHOLD);
+#endif
+
             if ( error_ratio_surr <= 0 )
             {
                 error_ratio_surr = 0;
@@ -8087,7 +8095,7 @@ static Word16 read_surround_coherence_hr_fx(
     Word16 coding_subbands;
     Word16 no_cv_vec[MASA_MAXIMUM_CODING_SUBBANDS];
     Word16 bit_pos;
-    Word32 error_ratio_surr_fx;
+    Word64 error_ratio_surr_fx;
     Word16 idx_ER[MASA_MAXIMUM_CODING_SUBBANDS];
     Word16 bits_sur_coherence, bits_GR;
     Word16 j, k, sf;
@@ -8096,6 +8104,7 @@ static Word16 read_surround_coherence_hr_fx(
     IVAS_QDIRECTION *q_direction;
     Word16 min_index;
     Word16 d, idx;
+    Word32 int_error_ratio_surr;
     coding_subbands = hQMetaData->q_direction[0].cfg.nbands;
     q_direction = hQMetaData->q_direction;
 
@@ -8105,63 +8114,24 @@ static Word16 read_surround_coherence_hr_fx(
     FOR( sf = 0; sf < hQMetaData->q_direction[0].cfg.nblocks; sf++ )
     {
         d = 0;
-#ifdef IVAS_FLOAT_FIXED_TBD
-        FOR( j = 0; j < coding_subbands; j++ )
-        {
-            error_ratio_surr_fx = 1 << *q;
-            if ( hQMetaData->no_directions == 2 )
-            {
-                d += hQMetaData->twoDirBands[j];
-                idx = max( d - 1, 0 );
-                error_ratio_surr_fx = L_sub(
-                    L_sub( 1 << *q, q_direction[0].band_data[j].energy_ratio_fx[sf] ),
-                    q_direction[1].band_data[idx].energy_ratio_fx[sf] * hQMetaData->twoDirBands[j] );
-            }
-            ELSE
-            {
-                error_ratio_surr_fx = L_sub( 1 << *q, q_direction[0].band_data[j].energy_ratio_fx[sf] );
-            }
 
-            if ( error_ratio_surr_fx <= 53667 ) // Assuming max error of 10^(-4) in q = 29 => 10^(-4) * 2^(29)
-            {
-                error_ratio_surr_fx = 0;
-                no_cv_vec[j] = 1;
-                idx_ER[j] = 0;
-            }
-            ELSE
-            {
-                idx_ER[j] = 7; // masa_sq( error_ratio_surr, diffuseness_thresholds, DIRAC_DIFFUSE_LEVELS );
-                no_cv_vec[j] = idx_cb_sur_coh_masa[idx_ER[j]] + 2;
-            }
-        }
-#else
-        /* NOTE: This block gives incorrect output with fixed point resulting in failures in pytest */
-        /* TODO: Remove the intermediate conversion from fixed to float below */
-        float tmp;
-        float energy_ratio_j_sf;
-        float energy_ratio_idx_sf;
         FOR( j = 0; j < coding_subbands; j++ )
         {
-            energy_ratio_j_sf = (float) energy_ratio[0][j][sf] / ( ONE_IN_Q62 );
-
-            tmp = 1.0f;
-            IF( hQMetaData->no_directions == 2 )
+            error_ratio_surr_fx = ONE_IN_Q62;
+            IF( EQ_32( hQMetaData->no_directions, 2 ) )
             {
-                d += hQMetaData->twoDirBands[j];
-                idx = max( d - 1, 0 );
-
-                energy_ratio_idx_sf = (float) energy_ratio[1][idx][sf] / ( ONE_IN_Q62 );
-
-                tmp = 1.0f - energy_ratio_j_sf - energy_ratio_idx_sf * hQMetaData->twoDirBands[j];
+                d = add( d, hQMetaData->twoDirBands[j] );
+                idx = s_max( sub( d, 1 ), 0 );
+                error_ratio_surr_fx = W_sub(
+                    W_sub( ONE_IN_Q62, energy_ratio[0][j][sf] ),
+                    energy_ratio[1][idx][sf] * hQMetaData->twoDirBands[j] );
             }
             ELSE
             {
-                tmp = 1.0f - energy_ratio_j_sf;
+                error_ratio_surr_fx = W_sub( ONE_IN_Q62, energy_ratio[0][j][sf] );
             }
 
-            error_ratio_surr_fx = (Word32) ( tmp * ONE_IN_Q30 );
-
-            IF( error_ratio_surr_fx <= 0 )
+            IF( LE_64( error_ratio_surr_fx, ( 461168601842 ) ) ) // 1e-7 in Q62
             {
                 error_ratio_surr_fx = 0;
                 no_cv_vec[j] = 1;
@@ -8173,9 +8143,8 @@ static Word16 read_surround_coherence_hr_fx(
                 no_cv_vec[j] = idx_cb_sur_coh_masa[idx_ER[j]] + 2;
             }
         }
-#endif // !IVAS_FLOAT_FIXED_TBD
 
-        IF( sum_s( no_cv_vec, coding_subbands ) == coding_subbands )
+        IF( EQ_16( sum_s( no_cv_vec, coding_subbands ), coding_subbands ) )
         {
             /* surround coherence is zero */
             FOR( j = 0; j < coding_subbands; j++ )
@@ -8193,29 +8162,29 @@ static Word16 read_surround_coherence_hr_fx(
         {
             /* read how the surround coherence is encoded */
             byteBuffer = bitstream[bit_pos--];
-            bits_sur_coherence += 1;
+            bits_sur_coherence = add( bits_sur_coherence, 1 );
 
             IF( byteBuffer & 1 )
             {
                 /* GR decoding */
                 /* read GR order */
                 byteBuffer = bitstream[bit_pos--];
-                bits_sur_coherence += 1;
+                bits_sur_coherence = add( bits_sur_coherence, 1 );
 
                 /* read min index */
                 bits_GR = bit_pos;
                 min_index = ivas_qmetadata_DecodeExtendedGR( bitstream, &bit_pos, MASA_MAX_NO_CV_SUR_COH, 0 );
-                bits_sur_coherence += bits_GR - bit_pos;
+                bits_sur_coherence = add( bits_sur_coherence, sub( bits_GR, bit_pos ) );
 
                 /* read GR data */
                 FOR( j = 0; j < coding_subbands; j++ )
                 {
                     bits_GR = bit_pos;
                     /* decoding for min removed */
-                    IF( no_cv_vec[j] > 1 )
+                    IF( GT_16( no_cv_vec[j], 1 ) )
                     {
                         idx_sur_coh[j] = ivas_qmetadata_DecodeExtendedGR( bitstream, &bit_pos, no_cv_vec[j] - min_index, ( byteBuffer & 1 ) );
-                        bits_sur_coherence += bits_GR - bit_pos;
+                        bits_sur_coherence = add( bits_sur_coherence, sub( bits_GR, bit_pos ) );
                     }
                     ELSE
                     {
@@ -8225,9 +8194,9 @@ static Word16 read_surround_coherence_hr_fx(
 
                 FOR( j = 0; j < coding_subbands; j++ )
                 {
-                    IF( no_cv_vec[j] > 1 )
+                    IF( GT_16( no_cv_vec[j], 1 ) )
                     {
-                        hQMetaData->surcoh_band_data[j].sur_coherence_index = idx_sur_coh[j] + min_index;
+                        hQMetaData->surcoh_band_data[j].sur_coherence_index = L_add( (Word32) idx_sur_coh[j], L_deposit_l( min_index ) );
                         hQMetaData->surcoh_band_data[j].surround_coherence[sf] = sur_coherence_cb_masa[idx_cb_sur_coh_masa[idx_ER[j]] * MASA_MAX_NO_CV_SUR_COH + hQMetaData->surcoh_band_data[j].sur_coherence_index];
                     }
                     ELSE
@@ -8253,7 +8222,7 @@ static Word16 read_surround_coherence_hr_fx(
                 /* deindex surround coherence */
                 FOR( j = 0; j < coding_subbands; j++ )
                 {
-                    IF( no_cv_vec[j] > 1 )
+                    IF( GT_16( no_cv_vec[j], 1 ) )
                     {
                         hQMetaData->surcoh_band_data[j].surround_coherence[sf] = sur_coherence_cb_masa[idx_cb_sur_coh_masa[idx_ER[j]] * MASA_MAX_NO_CV_SUR_COH + hQMetaData->surcoh_band_data[j].sur_coherence_index];
                     }
@@ -8267,7 +8236,7 @@ static Word16 read_surround_coherence_hr_fx(
     }
 
     /* Replace return value with the actual read bits. bits_sur_coherence might show wrong count at this point. */
-    bits_sur_coherence = *p_bit_pos - bit_pos;
+    bits_sur_coherence = sub( *p_bit_pos, bit_pos );
     *p_bit_pos = bit_pos;
 
     return bits_sur_coherence;
diff --git a/lib_dec/ivas_stereo_dft_dec.c b/lib_dec/ivas_stereo_dft_dec.c
index 711269dc514764acac0e6cd3a5169c5428bd021c..c7540036229895858cd8aad4d1c14bc86e21dd9f 100644
--- a/lib_dec/ivas_stereo_dft_dec.c
+++ b/lib_dec/ivas_stereo_dft_dec.c
@@ -3049,7 +3049,11 @@ void stereo_dft_dec_smooth_parameters(
         if ( hStereoDft->frame_sid_nodata )
         {
             /* set new xfade target if new itd received */
+#ifdef NONBE_FIX_1010_STEREO_CNG_DIV_BY_ZERO
+            if ( hStereoDft->ipd_xfade_counter < STEREO_DFT_ITD_CNG_XFADE )
+#else
             if ( hStereoDft->gipd[k + k_offset] != hStereoDft->ipd_xfade_target )
+#endif
             {
                 if ( ( hStereoDft->gipd[k + k_offset] - hStereoDft->ipd_xfade_prev ) > EVS_PI )
                 {
@@ -3095,7 +3099,11 @@ void stereo_dft_dec_smooth_parameters(
         if ( hStereoDft->frame_sid_nodata )
         {
             /* set new xfade target if new itd received */
+#ifdef NONBE_FIX_1010_STEREO_CNG_DIV_BY_ZERO
+            if ( hStereoDft->itd_xfade_counter < STEREO_DFT_ITD_CNG_XFADE )
+#else
             if ( hStereoDft->itd[k + k_offset] != hStereoDft->itd_xfade_target )
+#endif
             {
                 hStereoDft->itd_xfade_target = hStereoDft->itd[k + k_offset];
                 hStereoDft->itd_xfade_step = ( hStereoDft->itd_xfade_target - hStereoDft->itd_xfade_prev ) / ( STEREO_DFT_ITD_CNG_XFADE - hStereoDft->itd_xfade_counter );
diff --git a/lib_enc/ivas_qmetadata_enc.c b/lib_enc/ivas_qmetadata_enc.c
index 5e1c4597ed9e762ccacd841dc7a58e81bc951f74..5ca49dbbf4b909574cb27fdd472ee82a1573eae9 100644
--- a/lib_enc/ivas_qmetadata_enc.c
+++ b/lib_enc/ivas_qmetadata_enc.c
@@ -4515,6 +4515,9 @@ static int16_t encode_surround_coherence_hr(
     int16_t max_val = 0, nbits_max;
     int16_t no_cv_shift[MASA_MAXIMUM_CODING_SUBBANDS], min_idx;
     int16_t idx16;
+#ifdef NON_BE_FIX_1048_THRESHOLD_COH_BASOP
+    int32_t int_error_ratio_surr;
+#endif
 
     coding_subbands = hQMetaData->q_direction[0].cfg.nbands;
     all_coherence_zero = hQMetaData->all_coherence_zero;
@@ -4544,7 +4547,10 @@ static int16_t encode_surround_coherence_hr(
                 {
                     error_ratio_surr = 1.0f - q_direction[0].band_data[j].energy_ratio[sf];
                 }
-
+#ifdef NON_BE_FIX_1048_THRESHOLD_COH_BASOP
+                int_error_ratio_surr = (int32_t) ( MASA_SUR_COH_PRECISION * error_ratio_surr );
+                error_ratio_surr = (float) ( int_error_ratio_surr * MASA_SUR_COH_THRESHOLD );
+#endif
 
                 if ( error_ratio_surr <= 0 )
                 {
diff --git a/lib_rend/ivas_orient_trk.c b/lib_rend/ivas_orient_trk.c
index 0e92bf6b3410a3f2a8de2f1d65a4986dab89e1ad..a6d08f15b85d5465b3ef64e962f0beb148afa1fd 100644
--- a/lib_rend/ivas_orient_trk.c
+++ b/lib_rend/ivas_orient_trk.c
@@ -49,6 +49,10 @@
  *------------------------------------------------------------------------------------------*/
 
 #define OTR_UPDATE_RATE (float) FRAMES_PER_SEC /* rate of the Process() calls [Hz]; 1x per IVAS frame */
+#ifdef NONBE_FIX_738_QUATERNION_SLERP_PRECISION
+#define COS_ONE_TENTH_DEGREE ( 0.999998476913288f )
+#endif
+#define COS_ONE_TENTH_DEGREE_FX    2147480320  //Q31
 
 
 /*------------------------------------------------------------------------------------------*
@@ -298,21 +302,21 @@ static void QuaternionDivision_fx(
     IVAS_QUATERNION *const r,
     Word16 den_e )
 {
-    float den = me2f( d, den_e );
-    IVAS_QUATERNION q_flt;
-    Word16 e_temp;
-    q_flt.w = me2f( q.w_fx, 31 - q.w_qfact );
-    q_flt.x = me2f( q.x_fx, 31 - q.x_qfact );
-    q_flt.y = me2f( q.y_fx, 31 - q.y_qfact );
-    q_flt.z = me2f( q.z_fx, 31 - q.z_qfact );
-    f2me( ( q_flt.w / den ), &r->w_fx, &e_temp );
-    r->w_qfact = 31 - e_temp;
-    f2me( ( q_flt.x / den ), &r->x_fx, &e_temp );
-    r->x_qfact = 31 - e_temp;
-    f2me( ( q_flt.y / den ), &r->y_fx, &e_temp );
-    r->y_qfact = 31 - e_temp;
-    f2me( ( q_flt.z / den ), &r->z_fx, &e_temp );
-    r->z_qfact = 31 - e_temp;
+    Word16 scale_e, result_e = 0;
+    r->w_fx = L_deposit_h(BASOP_Util_Divide3232_Scale((q.w_fx), d, &scale_e));
+    result_e = scale_e + ((31 - q.w_qfact) - den_e); // e+e1-e2//
+    r->w_qfact = 31 - result_e;
+    r->x_fx = L_deposit_h(BASOP_Util_Divide3232_Scale((q.x_fx), d, &scale_e));
+    result_e = scale_e + ((31 - q.x_qfact) - den_e);
+    r->x_qfact = 31 - result_e;
+    r->y_fx = L_deposit_h(BASOP_Util_Divide3232_Scale((q.y_fx), d, &scale_e));
+    result_e = scale_e + ((31 - q.y_qfact) - den_e);
+    r->y_qfact = 31 - result_e;
+    r->z_fx = L_deposit_h(BASOP_Util_Divide3232_Scale((q.z_fx), d, &scale_e));
+    result_e = scale_e + ((31 - q.z_qfact) - den_e);
+    r->z_qfact = 31 - result_e;
+
+
 }
 #endif
 
@@ -355,85 +359,156 @@ static void QuaternionNormalize_fx(
  * Computes a spherical linear interpolation between two quaternions
  *------------------------------------------------------------------------------------------*/
 
+#ifndef IVAS_FLOAT_FIXED
 void QuaternionSlerp(
     const IVAS_QUATERNION q1,
     const IVAS_QUATERNION q2,
     const float t,
     IVAS_QUATERNION *const r )
 {
-    float angle, denom, s, s2;
+#ifdef NONBE_FIX_738_QUATERNION_SLERP_PRECISION
+    IVAS_QUATERNION r1, r2;
+    float phi, sinPhi, cosPhi, s1, s2;
 
-    s = QuaternionDotProduct( q1, q2 );
+    QuaternionNormalize( q1, &r1 );
+    QuaternionNormalize( q2, &r2 );
+
+    cosPhi = QuaternionDotProduct( r1, r2 );
 
-    if ( fabsf( s ) >= 1.0f )
+    if ( cosPhi < 0 )
     {
+        cosPhi = -cosPhi;
+        r2.w = -r2.w;
+        r2.x = -r2.x;
+        r2.y = -r2.y;
+        r2.z = -r2.z;
+    }
 
-        *r = q2;
-        return;
+    /* Angle less than one degree, use linear interpolation */
+    if ( cosPhi >= COS_ONE_TENTH_DEGREE )
+    {
+        r->w = r1.w + t * ( r2.w - r1.w );
+        r->x = r1.x + t * ( r2.x - r1.x );
+        r->y = r1.y + t * ( r2.y - r1.y );
+        r->z = r1.z + t * ( r2.z - r1.z );
     }
+    else
+    {
+        phi = acosf( cosPhi );
+        sinPhi = sinf( phi );
 
-    angle = acosf( s );
-    denom = sinf( angle );
+        s1 = sinf( ( 1 - t ) * phi );
+        s2 = sinf( t * phi );
 
-    s = sinf( ( 1 - t ) * angle );
-    s2 = sinf( t * angle );
-    r->x = ( q1.x * s + q2.x * s2 ) / denom;
+        r->w = ( s1 * r1.w + s2 * r2.w ) / sinPhi;
+        r->x = ( s1 * r1.x + s2 * r2.x ) / sinPhi;
+        r->y = ( s1 * r1.y + s2 * r2.y ) / sinPhi;
+        r->z = ( s1 * r1.z + s2 * r2.z ) / sinPhi;
+    }
+#else
+    float angle, denom, s, s2;
+
+    s = QuaternionDotProduct( q1, q2 );
     r->y = ( q1.y * s + q2.y * s2 ) / denom;
     r->z = ( q1.z * s + q2.z * s2 ) / denom;
     r->w = ( q1.w * s + q2.w * s2 ) / denom;
 
+#endif
     QuaternionNormalize( *r, r );
 
     return;
 }
 
-#ifdef IVAS_FLOAT_FIXED
+#else
 void QuaternionSlerp_fx(
     const IVAS_QUATERNION q1_fx,
     const IVAS_QUATERNION q2_fx,
     const Word32 t_fx,
     IVAS_QUATERNION *const r_fx )
 {
-    float angle, denom, s, s2;
-    float t = me2f( t_fx, 1 );
-    IVAS_QUATERNION q1, q2;
+    IVAS_QUATERNION r1, r2;
+    Word32 sinPhi, cosPhi, temp_32;
+    Word16 q_min, sin_e, phi, s1, s2, temp_16, e_div;
+
+    QuaternionNormalize_fx( q1_fx, &r1 );
+    QuaternionNormalize_fx( q2_fx, &r2 );
+
     Word16 q_dot = 0;
-    Word32 s_fx = QuaternionDotProduct_fx( q1_fx, q2_fx, &q_dot );
-    s = me2f( s_fx, 31 - q_dot );
+    cosPhi = QuaternionDotProduct_fx( r1, r2, &q_dot );
+
+    q_min = s_min( s_min( r1.w_qfact, r1.x_qfact ), s_min( r1.y_qfact, r1.z_qfact ) );
+    q_min = s_min( q_min, s_min( s_min( r1.w_qfact, r1.x_qfact ), s_min( r1.y_qfact, r1.z_qfact ) ) );
+    r1.w_fx = L_shr( r1.w_fx, sub( r1.w_qfact, q_min ) );
+    r1.x_fx = L_shr( r1.x_fx, sub( r1.x_qfact, q_min ) );
+    r1.y_fx = L_shr( r1.y_fx, sub( r1.y_qfact, q_min ) );
+    r1.z_fx = L_shr( r1.z_fx, sub( r1.z_qfact, q_min ) );
+    r2.w_fx = L_shr( r2.w_fx, sub( r2.w_qfact, q_min ) );
+    r2.x_fx = L_shr( r2.x_fx, sub( r2.x_qfact, q_min ) );
+    r2.y_fx = L_shr( r2.y_fx, sub( r2.y_qfact, q_min ) );
+    r2.z_fx = L_shr( r2.z_fx, sub( r2.z_qfact, q_min ) );
+    r1.w_qfact = r1.x_qfact = r1.y_qfact = r1.z_qfact = r2.w_qfact = r2.x_qfact = r2.y_qfact = r2.z_qfact = q_min;
+
+    IF( LT_32( cosPhi, 0 ) )
+    {
+        cosPhi = L_negate( cosPhi );
+        r2.w_fx = L_negate( r2.w_fx );
+        r2.x_fx = L_negate( r2.x_fx );
+        r2.y_fx = L_negate( r2.y_fx );
+        r2.z_fx = L_negate( r2.z_fx );
+    }
 
 
-    if ( fabsf( s ) >= 1.0f )
+    /* Angle less than one degree, use linear interpolation */
+    IF( GE_32( cosPhi, L_shr( COS_ONE_TENTH_DEGREE_FX, sub( 31, q_dot ) ) ) )
     {
-        *r_fx = q2_fx;
-        return;
+        r_fx->w_fx = L_add( L_shr( r1.w_fx, 1 ), Mpy_32_32( L_sub( r2.w_fx, r1.w_fx ), t_fx ) ); // q_min-1
+        r_fx->x_fx = L_add( L_shr( r1.x_fx, 1 ), Mpy_32_32( L_sub( r2.x_fx, r1.x_fx ), t_fx ) ); // q_min-1
+        r_fx->y_fx = L_add( L_shr( r1.y_fx, 1 ), Mpy_32_32( L_sub( r2.y_fx, r1.y_fx ), t_fx ) ); // q_min-1
+        r_fx->z_fx = L_add( L_shr( r1.z_fx, 1 ), Mpy_32_32( L_sub( r2.z_fx, r1.z_fx ), t_fx ) ); // q_min-1
+
+        r2.w_qfact = r2.x_qfact = r2.y_qfact = r2.z_qfact = sub( q_min, 1 );
     }
+    ELSE
+    {
+        temp_32 = L_sub( L_shr( ONE_IN_Q31, sub( 62, 2 * q_dot ) ), ( Mpy_32_32( cosPhi, cosPhi ) ) );
+        sin_e = sub( 62, 2 * q_dot );
+        sinPhi = Sqrt32( temp_32, &sin_e );
 
-    angle = acosf( s );
-    denom = sinf( angle );
-
-    s = sinf( ( 1 - t ) * angle );
-    s2 = sinf( t * angle );
-    q1.w = me2f( q1_fx.w_fx, 31 - q1_fx.w_qfact );
-    q1.x = me2f( q1_fx.x_fx, 31 - q1_fx.x_qfact );
-    q1.y = me2f( q1_fx.y_fx, 31 - q1_fx.y_qfact );
-    q1.z = me2f( q1_fx.z_fx, 31 - q1_fx.z_qfact );
-    q2.w = me2f( q2_fx.w_fx, 31 - q2_fx.w_qfact );
-    q2.x = me2f( q2_fx.x_fx, 31 - q2_fx.x_qfact );
-    q2.y = me2f( q2_fx.y_fx, 31 - q2_fx.y_qfact );
-    q2.z = me2f( q2_fx.z_fx, 31 - q2_fx.z_qfact );
-    r_fx->x = ( q1.x * s + q2.x * s2 ) / denom;
-    r_fx->y = ( q1.y * s + q2.y * s2 ) / denom;
-    r_fx->z = ( q1.z * s + q2.z * s2 ) / denom;
-    r_fx->w = ( q1.w * s + q2.w * s2 ) / denom;
-
-    r_fx->w_fx = float_to_fix(r_fx->w, Q29 );
-    r_fx->x_fx = float_to_fix(r_fx->x, Q29 );
-    r_fx->y_fx = float_to_fix(r_fx->y, Q29 );
-    r_fx->z_fx = float_to_fix(r_fx->z, Q29 );
-    r_fx->w_qfact = r_fx->x_qfact = r_fx->y_qfact = r_fx->z_qfact = Q29;
-    QuaternionNormalize_fx( *r_fx, r_fx );
+        phi = BASOP_util_atan2( sinPhi, cosPhi, sub( sin_e, sub( 31, q_dot ) ) ); // Q13
 
+        temp_32 = L_shl(Mpy_32_16_1( L_sub( ONE_IN_Q30, t_fx ), phi ),1); // Q29
+
+        temp_16 = extract_h( temp_32 );                 // Q13
+        s1 = getSineWord16R2( mult( temp_16, 20860 ) ); // Q15
+
+        temp_32 = L_shl(Mpy_32_16_1( t_fx, phi ),1);             // Q29
+        temp_16 = extract_h( temp_32 );                 // Q13
+        s2 = getSineWord16R2( mult( temp_16, 20860 ) ); // Q15
+
+        temp_32 = L_add( Mpy_32_16_1( r1.w_fx, s1 ), Mpy_32_16_1( r2.w_fx, s2 ) ); // q_min
+        r_fx->w_fx = L_deposit_h(BASOP_Util_Divide3232_Scale( temp_32, sinPhi, &e_div ));
+        e_div = e_div + ( 31 - q_min - sin_e );
+        r_fx->w_qfact = 31 - e_div;
+
+        temp_32 = L_add( Mpy_32_16_1( r1.x_fx, s1 ), Mpy_32_16_1( r2.x_fx, s2 ) ); // q_min
+        r_fx->x_fx = L_deposit_h(BASOP_Util_Divide3232_Scale( temp_32, sinPhi, &e_div ));
+        e_div = e_div + ( 31 - q_min - sin_e );
+        r_fx->x_qfact = 31 - e_div;
+
+        temp_32 = L_add( Mpy_32_16_1( r1.y_fx, s1 ), Mpy_32_16_1( r2.y_fx, s2 ) ); // q_min
+        r_fx->y_fx = L_deposit_h(BASOP_Util_Divide3232_Scale( temp_32, sinPhi, &e_div ));
+        e_div = e_div + ( 31 - q_min - sin_e );
+        r_fx->y_qfact = 31 - e_div;
+
+        temp_32 = L_add( Mpy_32_16_1( r1.z_fx, s1 ), Mpy_32_16_1( r2.z_fx, s2 ) ); // q_min
+        r_fx->z_fx = L_deposit_h(BASOP_Util_Divide3232_Scale( temp_32, sinPhi, &e_div ));
+        e_div = e_div + ( 31 - q_min - sin_e );
+        r_fx->z_qfact = 31 - e_div;
+    }
+
+    QuaternionNormalize_fx(*r_fx, r_fx);
     return;
+
 }
 #endif
 
diff --git a/lib_rend/ivas_rotation.c b/lib_rend/ivas_rotation.c
index 93b32afa105e1754ee3b9d4551d37eb11703d1a5..fcd93b3ac9cac41186303ae92260c4873383428c 100644
--- a/lib_rend/ivas_rotation.c
+++ b/lib_rend/ivas_rotation.c
@@ -1689,21 +1689,21 @@ ivas_error ivas_combined_orientation_open(
     identity.x = identity.y = identity.z = 0.0f;
     origo.x = origo.y = origo.z = 0.0f;
 #ifdef IVAS_FLOAT_FIXED
-    identity.w_fx = ONE_IN_Q30;
-    identity.w_qfact = 1;
+    identity.w_fx = ONE_IN_Q31;
+    identity.w_qfact = 31;
     identity.x_fx = 0;
-    identity.x_qfact = 1;
+    identity.x_qfact = 31;
     identity.y_fx = 0;
-    identity.y_qfact = 1;
+    identity.y_qfact = 31;
     identity.z_fx = 0;
-    identity.z_qfact = 1;
+    identity.z_qfact = 31;
 
     origo.x_fx = 0;
-    origo.x_qfact = 0;
+    origo.x_qfact = 31;
     origo.y_fx = 0;
-    origo.y_qfact = 0;
+    origo.y_qfact = 31;
     origo.z_fx = 0;
-    origo.z_qfact = 0;
+    origo.z_qfact = 31;
 #endif
 
     /* Allocate handle */
@@ -1980,7 +1980,31 @@ ivas_error combine_external_and_head_orientations(
                 if ( hCombinedOrientationData->isInterpolationOngoing == true && hCombinedOrientationData->interpolationCoefficient <= 1.0f && are_orientations_same( &hCombinedOrientationData->Quaternions_ext_interpolation_target, &hExtOrientationData->Quaternions[i] ) == true )
                 {
                     /* Continue interpolation */
-                    QuaternionSlerp( hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i] );
+#ifdef IVAS_FLOAT_FIXED
+                  hCombinedOrientationData->interpolationCoefficient_fx = float_to_fix(hCombinedOrientationData->interpolationCoefficient, Q30);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_start.w_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.w, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_start.x_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.x, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_start.y_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.y, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_start.z_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.z, Q29);
+
+                  hCombinedOrientationData->Quaternions_ext_interpolation_target.w_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.w, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_target.x_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.x, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_target.y_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.y, Q29);
+                  hCombinedOrientationData->Quaternions_ext_interpolation_target.z_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.z, Q29);
+
+                  hCombinedOrientationData->Quaternions_ext_interpolation_start.w_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.x_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.y_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.z_qfact = Q29;
+                  hCombinedOrientationData->Quaternions_ext_interpolation_target.w_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.x_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.y_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.z_qfact = Q29;
+
+                  QuaternionSlerp_fx(hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i]);
+
+                  hCombinedOrientationData->Quaternions[i].w = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].w_fx, hCombinedOrientationData->Quaternions[i].w_qfact);
+                  hCombinedOrientationData->Quaternions[i].x = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].x_fx, hCombinedOrientationData->Quaternions[i].x_qfact);
+                  hCombinedOrientationData->Quaternions[i].y = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].y_fx, hCombinedOrientationData->Quaternions[i].y_qfact);
+                  hCombinedOrientationData->Quaternions[i].z = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].z_fx, hCombinedOrientationData->Quaternions[i].z_qfact);
+
+#else
+                  QuaternionSlerp(hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i]);
+#endif
                     hCombinedOrientationData->interpolationCoefficient += hCombinedOrientationData->interpolationIncrement;
                 }
                 else
@@ -2231,7 +2255,31 @@ static void external_target_interpolation(
 
         /* Interpolate */
         hCombinedOrientationData->isInterpolationOngoing = TRUE;
-        QuaternionSlerp( hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i] );
+#ifdef IVAS_FLOAT_FIXED
+        hCombinedOrientationData->interpolationCoefficient_fx = float_to_fix(hCombinedOrientationData->interpolationCoefficient, Q30);
+        hCombinedOrientationData->Quaternions_ext_interpolation_start.w_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.w, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_start.x_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.x, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_start.y_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.y, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_start.z_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_start.z, Q29);
+
+        hCombinedOrientationData->Quaternions_ext_interpolation_target.w_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.w, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_target.x_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.x, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_target.y_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.y, Q29);
+        hCombinedOrientationData->Quaternions_ext_interpolation_target.z_fx = float_to_fix(hCombinedOrientationData->Quaternions_ext_interpolation_target.z, Q29);
+
+        hCombinedOrientationData->Quaternions_ext_interpolation_start.w_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.x_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.y_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_start.z_qfact = Q29;
+        hCombinedOrientationData->Quaternions_ext_interpolation_target.w_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.x_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.y_qfact = hCombinedOrientationData->Quaternions_ext_interpolation_target.z_qfact = Q29;
+
+        QuaternionSlerp_fx(hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i]);
+
+        hCombinedOrientationData->Quaternions[i].w = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].w_fx, hCombinedOrientationData->Quaternions[i].w_qfact);
+        hCombinedOrientationData->Quaternions[i].x = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].x_fx, hCombinedOrientationData->Quaternions[i].x_qfact);
+        hCombinedOrientationData->Quaternions[i].y = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].y_fx, hCombinedOrientationData->Quaternions[i].y_qfact);
+        hCombinedOrientationData->Quaternions[i].z = fixedToFloat_32(hCombinedOrientationData->Quaternions[i].z_fx, hCombinedOrientationData->Quaternions[i].z_qfact);
+
+#else
+        QuaternionSlerp(hCombinedOrientationData->Quaternions_ext_interpolation_start, hCombinedOrientationData->Quaternions_ext_interpolation_target, hCombinedOrientationData->interpolationCoefficient, &hCombinedOrientationData->Quaternions[i]);
+#endif
         hCombinedOrientationData->interpolationCoefficient += hCombinedOrientationData->interpolationIncrement;
     }
     else
diff --git a/lib_rend/ivas_stat_rend.h b/lib_rend/ivas_stat_rend.h
index d3348f9dda1beb88aec6fc8a1153756f85131a53..677ca58fe3dc6bafb7689a7b9910a4b2c0da0d73 100644
--- a/lib_rend/ivas_stat_rend.h
+++ b/lib_rend/ivas_stat_rend.h
@@ -1104,6 +1104,8 @@ typedef struct ivas_combined_orientation_struct
     float procChEneIIR[2][MASA_FREQUENCY_BANDS];
 #ifdef IVAS_FLOAT_FIXED
     Word32 lrSwitchInterpVal_fx;
+    Word32 interpolationCoefficient_fx;
+    Word32 interpolationIncrement_Fx;
     Word32 chEneIIR_fx[2][MASA_FREQUENCY_BANDS]; /* independent of the format. MASA bands are suitable for the task and readily available in ROM. */
     Word16 q_chEneIIR;
     Word32 procChEneIIR_fx[2][MASA_FREQUENCY_BANDS];