diff --git a/lib_enc/ivas_mc_paramupmix_enc.c b/lib_enc/ivas_mc_paramupmix_enc.c
index 4c454a67b6126aef2836dc08a17363155a2da981..e51703ea359608ca3a18edf3a73ed76816b56a47 100644
--- a/lib_enc/ivas_mc_paramupmix_enc.c
+++ b/lib_enc/ivas_mc_paramupmix_enc.c
@@ -809,13 +809,18 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
     move16();
     move16();
     move16();
+    move16();
+    move16();
+    move16();
+    move16();
+    move16();
+    move16();
+    move16();
 
     FOR( i = 0; i < MC_PARAMUPMIX_COMBINATIONS; i++ )
     {
         pcm_in_fx[2 * i] = data_f_fx[chan1s[i]];
         pcm_in_fx[2 * i + 1] = data_f_fx[chan2s[i]];
-        move16();
-        move16();
 
         Scale_sig32( pcm_in_fx[2 * i], input_frame, sub( Q14, Q_data_f ) );
         Scale_sig32( pcm_in_fx[2 * i + 1], input_frame, sub( Q14, Q_data_f ) );
@@ -842,8 +847,6 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
     {
         p_fr_realbuffer_fx[i] = fr_realbuffer_fx[i];
         p_fr_imagbuffer_fx[i] = fr_imagbuffer_fx[i];
-        move32();
-        move32();
     }
 
     /* prepare Parameter MDFT analysis */
@@ -851,8 +854,6 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
     {
         pp_in_fr_real_fx[i] = p_fr_realbuffer_fx[i];
         pp_in_fr_imag_fx[i] = p_fr_imagbuffer_fx[i];
-        move32();
-        move32();
     }
 
     // l_ts = input_frame / MAX_PARAM_SPATIAL_SUBFRAMES;
@@ -887,8 +888,8 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
 
     FOR( i = 0; i < MC_PARAMUPMIX_COMBINATIONS; i++ )
     {
-        Scale_sig32( pcm_in_fx[2 * i], input_frame, Q_data_f - Q14 );
-        Scale_sig32( pcm_in_fx[2 * i + 1], input_frame, Q_data_f - Q14 );
+        Scale_sig32( pcm_in_fx[2 * i], input_frame, sub( Q_data_f, Q14 ) );
+        Scale_sig32( pcm_in_fx[2 * i + 1], input_frame, sub( Q_data_f, Q14 ) );
     }
 
     /*-----------------------------------------------------------------------------------------*
@@ -953,15 +954,14 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
         FOR( bnd = 0; bnd < maxbands; bnd++ )
         {
             rxy_fx = hMCParamUpmix->cov_real_fx[b][1][0][bnd];
+            move32();
             ryy_fx = hMCParamUpmix->cov_real_fx[b][1][1][bnd];
+            move32();
 
-            Word16 exp_tmp = 0;
-            move16();
-            Word32 tmp = BASOP_Util_Add_Mant32Exp( ryy_fx, sub( 31, ( hMCParamUpmix->hCovEnc[b]->pCov_state->q_cov_real_per_band[1][1][bnd] ) ), EPSILON_FX_M, EPSILON_FX_E, &exp_tmp );
             exp_cmat = 0;
             move16();
-            cmat_fx = BASOP_Util_Divide3232_Scale( rxy_fx, tmp, &exp_cmat );
-            exp_cmat = sub( add( exp_cmat, sub( 31, ( hMCParamUpmix->hCovEnc[b]->pCov_state->q_cov_real_per_band[1][0][bnd] ) ) ), exp_tmp );
+            cmat_fx = BASOP_Util_Divide3232_Scale( rxy_fx, L_add( ryy_fx, EPSILON_FX ), &exp_cmat );
+            exp_cmat = sub( add( exp_cmat, sub( 31, ( hMCParamUpmix->hCovEnc[b]->pCov_state->q_cov_real_per_band[1][0][bnd] ) ) ), sub( 31, ( hMCParamUpmix->hCovEnc[b]->pCov_state->q_cov_real_per_band[1][1][bnd] ) ) );
 
             Word16 alpha_fx = 0, exp_alpha_var = 0;
             move16();
@@ -969,6 +969,7 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
             exp_alpha_var = BASOP_Util_Add_MantExp( cmat_fx, add( exp_cmat, 1 ), negate( ONE_IN_Q14 ), 1, &alpha_fx );
 
             rxx_fx = hMCParamUpmix->cov_real_fx[b][0][0][bnd];
+            move32();
             Word32 tmp_2 = L_mult( cmat_fx, cmat_fx ); // exp_cmat * 2
             rxxest_fx = Mpy_32_32( tmp_2, ryy_fx );
 
@@ -980,8 +981,8 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
 
             exp_wetaux = 0;
             move16();
-            wetaux_fx = BASOP_Util_Divide3232_Scale( drxx_fx, tmp, &exp_wetaux );
-            exp_wetaux = sub( add( exp_wetaux, exp_drxx ), exp_tmp );
+            wetaux_fx = BASOP_Util_Divide3232_Scale( drxx_fx, L_add( ryy_fx, EPSILON_FX ), &exp_wetaux );
+            exp_wetaux = sub( add( exp_wetaux, exp_drxx ), sub( 31, ( hMCParamUpmix->hCovEnc[b]->pCov_state->q_cov_real_per_band[1][1][bnd] ) ) );
 
             Word16 sqrt_wetaux_fx = 0, exp_sqrt_wetaux = 0;
             move16();
@@ -993,10 +994,6 @@ static ivas_error ivas_mc_paramupmix_param_est_enc_fx(
                 move16();
                 move16();
                 BASOP_Util_Sqrt_InvSqrt_MantExp( wetaux_fx, exp_wetaux, &sqrt_wetaux_fx, &exp_sqrt_wetaux, &tmp_4, &exp_tmp4 );
-                tmp_4 = tmp_4;
-                exp_tmp4 = exp_tmp4;
-                move16();
-                move16();
             }
             ELSE
             {