diff --git a/apps/renderer.c b/apps/renderer.c
index 242b80fbfe49420e6d0397a4221e4c1de5b96985..5917e4d29a89aa14e3ce6f240e3a3a4134bdb634 100644
--- a/apps/renderer.c
+++ b/apps/renderer.c
@@ -49,6 +49,7 @@
 #include "split_rend_bfi_file_reader.h"
 #include "vector3_pair_file_reader.h"
 #include "wmc_auto.h"
+#include "basop32.h"
 
 
 #define WMC_TOOL_SKIP
diff --git a/lib_com/basop32.c b/lib_com/basop32.c
index 6a34cff43e570ae4a6a3212891067ca5887bef48..eebc1684915ccba9a062a49f561a112f2208d36d 100644
--- a/lib_com/basop32.c
+++ b/lib_com/basop32.c
@@ -1268,7 +1268,7 @@ Word16 round_fx( Word32 L_var1 )
     Word32 L_rounded;
 
     BASOP_SATURATE_WARNING_OFF
-    L_rounded = L_add( L_var1, (Word32) 0x00008000L );
+    L_rounded = L_add_sat( L_var1, (Word32) 0x00008000L );
     BASOP_SATURATE_WARNING_ON
     var_out = extract_h( L_rounded );
 
diff --git a/lib_com/basop_util.c b/lib_com/basop_util.c
index ee959cf6f3320476902e45215ee49b6872d4ed69..bb92e286f399aa6f44d24ccab9abc17adb05ae18 100644
--- a/lib_com/basop_util.c
+++ b/lib_com/basop_util.c
@@ -2085,6 +2085,8 @@ Word32 norm_llQ31(               /* o : normalized result              Q31 */
     return L_sum;
 }
 
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
+/* note: now available in basop_util.h */
 Word32 w_norm_llQ31( Word64 L_sum, Word16 *exp );
 Word32 w_norm_llQ31(               /* o : normalized result              Q31 */
                      Word64 L_sum, /* i : upper and lower bits of accu, unsigned   Q31 */
@@ -2111,6 +2113,7 @@ Word32 w_norm_llQ31(               /* o : normalized result              Q31 */
     L_tmp = W_extract_h( L64_inp64 );
     return L_tmp;
 }
+#endif
 
 Word32 Dot_product16HQ(                     /* o : normalized result              Q31 */
                         const Word32 L_off, /* i : initial sum value               Qn */
@@ -2135,6 +2138,24 @@ Word32 Dot_product16HQ(                     /* o : normalized result
     return L_sum;
 }
 
+Word32 sum_array_norm(                   /* o : normalized result              Q31 */
+                       const Word32 x[], /* i : x vector                        Qn */
+                       const Word16 lg,  /* i : vector length, range [0..7FFF]  Q0 */
+                       Word16 *exp       /* o : exponent of result in [-32,31]  Q0 */
+)
+{
+    Word16 i;
+    Word64 W_tmp = 0;
+    Word32 L_tmp;
+    FOR( i = 0; i < lg; i++ )
+    {
+        W_tmp = W_add( W_tmp, x[i] ); /*Q31*/
+    }
+    L_tmp = w_norm_llQ31( W_tmp, exp ); /*Q31 - *exp*/
+    return L_tmp;
+}
+
+
 Word32 Norm32Norm( const Word32 *x, const Word16 headroom, const Word16 length, Word16 *result_e )
 {
     Word32 L_tmp, L_tmp2;
diff --git a/lib_com/basop_util.h b/lib_com/basop_util.h
index c95bf8100c976ed26819a27e1141278398ee098a..0a82d112d46338b3259f53939c4f40407ff980f3 100644
--- a/lib_com/basop_util.h
+++ b/lib_com/basop_util.h
@@ -612,6 +612,20 @@ Word32 Dot_product16HQ(                     /*<! o : normalized result
                         Word16 *exp         /*<! o : exponent of result in [-32,31]  Q0 */
 );
 
+/*------------------------------------------------------------------*
+ * sum_array_norm:
+ *
+ * \brief Compute array summation of x[] using 64-bit accumulator.
+ *
+ * Performs normalization of the result, returns the exponent
+ * Note: no headroom is required for data in x[]
+ *------------------------------------------------------------------*/
+Word32 sum_array_norm(                   /* o : normalized result              Q31 */
+                       const Word32 x[], /* i : x vector                        Qn */
+                       const Word16 lg,  /* i : vector length, range [0..7FFF]  Q0 */
+                       Word16 *exp       /* o : exponent of result in [-32,31]  Q0 */
+);
+
 /*------------------------------------------------------------------*
  * norm_llQ31:
  *
@@ -627,6 +641,23 @@ Word32 norm_llQ31(               /* o : normalized result              Q31 */
                    Word16 *exp   /* o : exponent of result in [-32,31]  Q0 */
 );
 
+#ifdef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
+/*------------------------------------------------------------------*
+ * w_norm_llQ31:
+ *
+ * \brief Compute normalized Q31 Values out of overflowed Q31 value
+ *        using 64-bit operators
+ *------------------------------------------------------------------*/
+static inline Word32 w_norm_llQ31( Word64 L64_var1, Word16 *S_var2 ) /*Q31 - L_tmp_exp*/
+{
+    Word32 L_result;
+    Word16 sh = W_norm( L64_var1 );
+    L_result = W_extract_h( W_shl( L64_var1, sh ) );
+    *S_var2 = ( L_result == 0 ) ? -32 : 32 - sh;
+    return L_result;
+}
+#endif
+
 /**
  * \brief Compute dot product of 1 32 bit vectors with itself
  * \param x input vector 1
diff --git a/lib_com/options.h b/lib_com/options.h
index 0a0e38e5fdd51fee2b0b6fe39fd803b527569e3b..065e4bdffdd56f83fd277ff643147572ae38ff0b 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -90,6 +90,7 @@
 #define FIX_1824
 #define FIX_1822
 
+#define FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW  /* FhG: bit-exact, replace carry and overflow operations by 64-bit operations, MR 1931 */
 #define FIX_1844_MISSING_FREE                                /* FhG: add missing free in ivas_binRenderer_convModuleClose_fx() */
 
 /* #################### Start BASOP porting switches ############################ */
diff --git a/lib_dec/dec_tcx_fx.c b/lib_dec/dec_tcx_fx.c
index c0a099b87e6eb0bab02797146919f6f8d8c7b9e5..d1d290b86f8fd35af06008949990ac1a6b9f90f9 100644
--- a/lib_dec/dec_tcx_fx.c
+++ b/lib_dec/dec_tcx_fx.c
@@ -6,9 +6,9 @@
 #include <stdio.h>
 #include <assert.h>
 #include "prot_fx.h"
+#include "options.h"
 #include "basop_util.h"
 #include "stl.h"
-#include "options.h"
 #include "math.h"
 #include "ivas_prot_fx.h"
 #include "rom_com.h"
@@ -1859,6 +1859,7 @@ static Word32 CalculateAbsEnergy_fx(                     /* o : normalized resul
                                      const Word16 lg,    /* i : vector length, range [0..7FFF]  Q0 */
                                      Word16 *exp         /* o : exponent of result in [-32,31]  Q0 */
 )
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
 {
     Word16 i;
     Word32 L_sum, L_c;
@@ -1895,7 +1896,22 @@ static Word32 CalculateAbsEnergy_fx(                     /* o : normalized resul
     L_sum = norm_llQ31( L_c, L_sum, exp );
     return L_sum;
 }
+#else
+{
+    Word16 i;
+    Word32 L_sum;
+    Word64 L_sum64;
+
+    L_sum64 = W_deposit32_l( L_off );
 
+    FOR( i = 0; i < lg; i += 2 )
+    {
+        L_sum64 = W_mac_16_16( L_sum64, x[i], x[i] );
+    }
+    L_sum = w_norm_llQ31( L_sum64, exp ); /*Q31 - *exp */
+    return L_sum;
+}
+#endif /* FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW */
 
 void IMDCT_fx( Word32 *x, Word16 x_e, Word16 *old_syn_overl, Word16 *syn_Overl_TDAC, Word16 *xn_buf, const Word16 *tcx_aldo_window_1, const PWord16 *tcx_aldo_window_1_trunc, const PWord16 *tcx_aldo_window_2, const PWord16 *tcx_mdct_window_half, const PWord16 *tcx_mdct_window_minimum, const PWord16 *tcx_mdct_window_trans, Word16 tcx_mdct_window_half_length, Word16 tcx_mdct_window_min_length, Word16 index, Word16 left_rect, Word16 tcx_offset, Word16 overlap, Word16 L_frame, Word16 L_frameTCX, Word16 L_spec_TCX5, Word16 L_frame_glob, Word16 frame_cnt, Word16 bfi, Word16 *old_out, Word16 *Q_old_wtda, Decoder_State *st, Word16 fullbandScale, Word16 *acelp_zir )
 {
diff --git a/lib_dec/fd_cng_dec_fx.c b/lib_dec/fd_cng_dec_fx.c
index 416b9c716c9f2d58245067be8072d25f5a7ca44c..1e78b792becb0373958b675bf9a4995e0e4fd819 100644
--- a/lib_dec/fd_cng_dec_fx.c
+++ b/lib_dec/fd_cng_dec_fx.c
@@ -576,13 +576,17 @@ Word16 ApplyFdCng_fx(
     Word16 facTab[NPART];
     Word16 facTabExp[NPART];
     Word16 tmp_loop;
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
     Word32 L_c;
+#endif
     Word16 lsp_cng[M];
     HANDLE_FD_CNG_DEC hFdCngDec;
     HANDLE_FD_CNG_COM hFdCngCom;
 #ifdef BASOP_NOGLOB_DECLARE_LOCAL
     Flag Overflow = 0;
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
     Flag Carry = 0;
+#endif
     move16();
     move16();
 #endif
@@ -794,6 +798,7 @@ Word16 ApplyFdCng_fx(
                 {
 
                     tmp_loop = sub( hFdCngCom->stopFFTbin, hFdCngCom->startBand );
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
                     L_tmp = L_deposit_h( 0 );
                     L_c = L_deposit_h( 0 );
                     FOR( j = 0; j < tmp_loop; j++ )
@@ -826,6 +831,19 @@ Word16 ApplyFdCng_fx(
                     st->hTcxDec->conCngLevelBackgroundTrace = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
                     move16();
                     L_tmp_exp = add( L_tmp_exp, 1 );
+#else
+                    L_tmp = sum_array_norm( cngNoiseLevel, tmp_loop, &L_tmp_exp ); /*Q31 - L_tmp_exp*/
+                    L_tmp_exp = sub( add( L_tmp_exp, *cngNoiseLevel_exp ), 1 );
+
+                    L_tmp = L_shr( L_tmp, 15 ); /*Q16 - L_tmp_exp*/
+
+                    L_tmp = Mpy_32_16_1( L_tmp, shr( T_DIV_L_Frame[L_shl( L_mac( -28000, NORM_MDCT_FACTOR, 95 ), 1 - 15 )], 1 ) ); /*Q16,exp -7*/
+                    L_tmp_exp = add( L_tmp_exp, -7 + ( 31 - 16 ) );                                                                /*->Q31, L_tmp_exp*/
+
+                    st->hTcxDec->conCngLevelBackgroundTrace = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
+                    move16();
+                    L_tmp_exp = add( L_tmp_exp, 1 );
+#endif
                     st->hTcxDec->conCngLevelBackgroundTrace_e = L_tmp_exp;
                     move16();
                 }
@@ -833,6 +851,7 @@ Word16 ApplyFdCng_fx(
                 {
 
                     tmp_loop = sub( hFdCngCom->stopFFTbin, hFdCngCom->startBand );
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
                     L_tmp = L_deposit_h( 0 );
                     L_c = L_deposit_h( 0 );
                     FOR( j = 0; j < tmp_loop; j++ )
@@ -863,12 +882,25 @@ Word16 ApplyFdCng_fx(
                     L_tmp_exp = add( L_tmp_exp, 31 - 16 );                                                          /*->Q31, L_tmp_exp*/
 
                     st->hTcxDec->conCngLevelBackgroundTrace = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
+#else
+                    L_tmp = sum_array_norm( cngNoiseLevel, tmp_loop, &L_tmp_exp );
+                    L_tmp_exp = sub( add( L_tmp_exp, *cngNoiseLevel_exp ), 1 );
+
+                    L_tmp = Mpy_32_16_1( L_tmp, hFdCngCom->fftlen ); /*Q16 - L_tmp_exp*/
+
+                    L_tmp = Mpy_32_16_1( L_tmp, T_DIV_L_Frame[L_shl( L_mac( -28000, st->L_frame, 95 ), 1 - 15 )] ); /*Q16,exp -7*/
+                    L_tmp_exp = add( L_tmp_exp, -7 + ( 31 - 16 ) );                                                 /*->Q31, L_tmp_exp*/
+
+
+                    st->hTcxDec->conCngLevelBackgroundTrace = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
+#endif
                     move16();
                     st->hTcxDec->conCngLevelBackgroundTrace_e = L_tmp_exp;
                     move16();
                 }
 
                 tmp_loop = sub( hFdCngCom->stopFFTbin, hFdCngCom->startBand );
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
                 L_tmp = L_deposit_h( 0 );
                 L_c = L_deposit_h( 0 );
                 FOR( j = 0; j < tmp_loop; j++ )
@@ -900,6 +932,19 @@ Word16 ApplyFdCng_fx(
 
                 st->cngTDLevel = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
                 move16();
+#else
+                L_tmp = sum_array_norm( cngNoiseLevel, tmp_loop, &L_tmp_exp );                             /*Q31 - L_tmp_exp*/
+                L_tmp_exp = sub( add( L_tmp_exp, *cngNoiseLevel_exp ), 1 );
+
+                L_tmp = Mpy_32_16_1( L_tmp, hFdCngCom->fftlen ); /*Q16 - L_tmp_exp*/
+
+                L_tmp = Mpy_32_16_1( L_tmp, T_DIV_L_Frame[L_shr( L_mac( -28000, st->L_frame, 95 ), 15 - 1 )] ); /*Q16,exp -7*/
+                L_tmp_exp = add( L_tmp_exp, -7 + ( 31 - 16 ) );                                                 /*->Q31, L_tmp_exp */
+
+                st->cngTDLevel = round_fx_sat( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
+                move16();
+
+#endif
                 st->cngTDLevel_e = L_tmp_exp;
                 move16();
             }
@@ -1018,6 +1063,7 @@ Word16 ApplyFdCng_fx(
 
                 /*st->cngTDLevel = (float)sqrt( (sumFLOAT(cngNoiseLevel, hFdCngCom->stopFFTbin - hFdCngCom->startBand) / 2 * hFdCngCom->fftlen) / st->Mode2_L_frame);*/
                 tmp_loop = sub( hFdCngCom->stopFFTbin, hFdCngCom->startBand );
+#ifndef FIX_ISSUE_1817_REPLACE_CARRY_OVERFLOW
                 L_tmp = L_deposit_h( 0 );
                 L_c = L_deposit_h( 0 );
                 FOR( j = 0; j < tmp_loop; j++ )
@@ -1049,6 +1095,18 @@ Word16 ApplyFdCng_fx(
 
                 st->cngTDLevel = round_fx_o( Sqrt32( L_tmp, &L_tmp_exp ), &Overflow ); /*Q15 - L_tmp_exp*/
                 move16();
+#else
+                L_tmp = sum_array_norm( cngNoiseLevel, tmp_loop, &L_tmp_exp ); /*Q31 - L_tmp_exp*/
+                L_tmp_exp = sub( add( L_tmp_exp, *cngNoiseLevel_exp ), 1 );
+
+                L_tmp = Mpy_32_16_1( L_tmp, hFdCngCom->fftlen ); /*Q16 - L_tmp_exp*/
+
+                L_tmp = Mpy_32_16_1( L_tmp, T_DIV_L_Frame[L_shl( L_mac( -28000, st->L_frame, 95 ), 1 - 15 )] ); /*Q16,exp -7*/
+                L_tmp_exp = add( L_tmp_exp, -7 + ( 31 - 16 ) );                                                 /*->Q31, L_tmp_exp*/
+
+                st->cngTDLevel = round_fx( Sqrt32( L_tmp, &L_tmp_exp ) ); /*Q15 - L_tmp_exp*/
+                move16();
+#endif
                 st->cngTDLevel_e = L_tmp_exp;
                 move16();
                 BREAK;