diff --git a/lib_com/options.h b/lib_com/options.h
index 0f464530e07c877e3d207bfb6a183a8827c79fcf..56282bb4a7e4c5f2769e2ea451eb2b5e519a66ce 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -123,6 +123,14 @@
 #define FIX_1735_W_SHL_SAT_L                    /* FhG: Usage of W_shl_sat_l() */
 #define FIX_ISSUE_1792                          /* FhG: fix noise bursts in binaural rendering */
 
+/* Info for issue 1816:
+ * Some compilers do not automatically use 32 bit for 16x16bit products. The code "Word32 c = (Word16) a * (Word16) b;" creates then a 16-bit result, sign-extending the
+ * lower 16-bit of the product, any upper bits are omitted. Example: Product 0x0100 * 0x0100 results in 0x0001.0000, gets truncated to its lower bits and return 0x0000.
+ * The issue is fixed by simply casting one of the product operands to Word32 in lib_com/basop32.c
+ */
+#define FIX_ISSUE_1816_USE_W32_FOR_MPY_W16xW16          /* FhG: (QA-FIX) Use doubled data width for 16x16 product, some compilers keep 16-bit format also for products */
+#define FIX_ISSUE_1816_IMPROVE_MPY_ZERO_DOT_1_PRECISION /* FhG: (NON-BE) improve precision of multiplications with factor 0.1f, avoids overflow with up-rounded value */
+
 #define FIX_ISSUE_1795_Q3_OVERFLOW              /* FhG: Q3 overflow in function WB_BWE_gain_pred_fx (EVS legacy code) BE, MR1855 */
 #define NONBE_FIX_1748_SPAR_DIV_OPT                      /*Dlb: issue 1748: SPAR common div optimizations*/
 
diff --git a/lib_dec/swb_tbe_dec_fx.c b/lib_dec/swb_tbe_dec_fx.c
index 61dc3d0c56749685434360b3a72d0e8d6498a914..3ed08633c76d6e135dda5df6ae2f2b069adddf94 100644
--- a/lib_dec/swb_tbe_dec_fx.c
+++ b/lib_dec/swb_tbe_dec_fx.c
@@ -2723,6 +2723,38 @@ void swb_tbe_dec_fx(
         exp = 0;
         move16();
     }
+#ifdef FIX_ISSUE_1816_IMPROVE_MPY_ZERO_DOT_1_PRECISION
+    /*
+       code for EVS and IVAS are basically identical with the exception of i_mult_sat() which has precision issues
+       thus is was replaced for IVAS and kept for EVS, in order to keep EVS BE to test sequences and legacy implementations
+    */
+    IF( EQ_16( st_fx->element_mode, EVS_MONO ) )
+    {
+        FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+        {
+            temp = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );        /* Q15 */
+            L_tmp1 = Mult_32_16( L_shl_sat( 1, sub( 31, exp ) ), temp ); /* Q31-exp */
+            temp = sub( 32767 /*1.0f Q15*/, temp );
+            Lscale = L_add( Mult_32_16( Lscale, temp ), L_tmp1 );
+            L_tmp = Mult_32_16( Lscale, shaped_shb_excitation[i] );     /* Q_bwe_exc + (31-exp) - 15 */
+            shaped_shb_excitation[i] = round_fx( L_shl( L_tmp, exp ) ); /* Q_bwe_exc */
+            move16();
+        }
+    }
+    ELSE
+    {
+        FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+        {
+            temp = round_fx_sat( L_shl( L_mult( 0x6666 /* 0.1 in Q12 */, shl( sub( i, 19 ), 11 ) ), 1 ) );
+            L_tmp1 = Mult_32_16( L_shl_sat( 1, sub( 31, exp ) ), temp ); /* Q31-exp */
+            temp = sub( 32767 /*1.0f Q15*/, temp );
+            Lscale = L_add( Mult_32_16( Lscale, temp ), L_tmp1 );
+            L_tmp = Mult_32_16( Lscale, shaped_shb_excitation[i] );     /* Q_bwe_exc + (31-exp) - 15 */
+            shaped_shb_excitation[i] = round_fx( L_shl( L_tmp, exp ) ); /* Q_bwe_exc */
+            move16();
+        }
+    }
+#else
     FOR( ; i < L_SHB_LAHEAD + 10; i++ )
     {
         temp = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );        /* Q15 */
@@ -2733,6 +2765,7 @@ void swb_tbe_dec_fx(
         shaped_shb_excitation[i] = round_fx( L_shl( L_tmp, exp ) ); /* Q_bwe_exc */
         move16();
     }
+#endif
 
     /* Update SHB excitation */
     Copy( shaped_shb_excitation + L_FRAME16k, hBWE_TD->state_syn_shbexc_fx, L_SHB_LAHEAD ); /* Q_bwe_exc */
@@ -6285,6 +6318,38 @@ void ivas_swb_tbe_dec_fx(
             exp = 0;
             move16();
         }
+#ifdef FIX_ISSUE_1816_IMPROVE_MPY_ZERO_DOT_1_PRECISION
+        /*
+           code for EVS and IVAS are basically identical with the exception of i_mult_sat() which has precision issues
+           thus is was replaced for IVAS and kept for EVS, in order to keep EVS BE to test sequences and legacy implementations
+        */
+        IF( EQ_16( st->element_mode, EVS_MONO ) )
+        {
+            FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+            {
+                temp_fx = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );        /* Q15 */
+                L_tmp1 = Mult_32_16( L_shl_sat( 1, sub( 31, exp ) ), temp_fx ); /* Q31-exp */
+                temp_fx = sub( 32767 /*1.0f Q15*/, temp_fx );
+                Lscale = L_add( Mult_32_16( Lscale, temp_fx ), L_tmp1 );
+                L_tmp = Mult_32_16( Lscale, shaped_shb_excitation_fx[i] );             /* Q_bwe_exc + (31-exp) - 15 */
+                shaped_shb_excitation_fx[i] = round_fx_sat( L_shl_sat( L_tmp, exp ) ); /* Q_bwe_exc */
+                move16();
+            }
+        }
+        ELSE
+        {
+            FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+            {
+                temp_fx = round_fx_sat( L_shl( L_mult( 0x6666 /* 0.1 in Q12 */, shl( sub( i, 19 ), 11 ) ), 1 ) );
+                L_tmp1 = Mult_32_16( L_shl_sat( 1, sub( 31, exp ) ), temp_fx ); /* Q31-exp */
+                temp_fx = sub( 32767 /*1.0f Q15*/, temp_fx );
+                Lscale = L_add( Mult_32_16( Lscale, temp_fx ), L_tmp1 );
+                L_tmp = Mult_32_16( Lscale, shaped_shb_excitation_fx[i] );             /* Q_bwe_exc + (31-exp) - 15 */
+                shaped_shb_excitation_fx[i] = round_fx_sat( L_shl_sat( L_tmp, exp ) ); /* Q_bwe_exc */
+                move16();
+            }
+        }
+#else
         FOR( ; i < L_SHB_LAHEAD + 10; i++ )
         {
             temp_fx = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );        /* Q15 */
@@ -6295,6 +6360,7 @@ void ivas_swb_tbe_dec_fx(
             shaped_shb_excitation_fx[i] = round_fx_sat( L_shl_sat( L_tmp, exp ) ); /* Q_bwe_exc */
             move16();
         }
+#endif
     }
     ELSE
     {
diff --git a/lib_enc/swb_tbe_enc_fx.c b/lib_enc/swb_tbe_enc_fx.c
index d016cd7216d58c7d8fcaccee58ea5994442c9f01..e1bbd3e19207c57baccfd7570c1cb54340112e0f 100644
--- a/lib_enc/swb_tbe_enc_fx.c
+++ b/lib_enc/swb_tbe_enc_fx.c
@@ -2535,6 +2535,38 @@ void swb_tbe_enc_fx(
         exp = 0;
         move16();
     }
+#ifdef FIX_ISSUE_1816_IMPROVE_MPY_ZERO_DOT_1_PRECISION
+    /*
+       code for EVS and IVAS are basically identical with the exception of i_mult_sat() which has precision issues
+       thus is was replaced for IVAS and kept for EVS, in order to keep EVS BE to test sequences and legacy implementations
+    */
+    IF( EQ_16( st_fx->element_mode, EVS_MONO ) )
+    {
+        FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+        {
+            tmp = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );                 /* Q15 */
+            L_tmp1 = Mult_32_16( L_shl_o( 1, sub( 31, exp ), &Overflow ), tmp ); /* Q31-exp */
+            tmp = sub( 32767 /*1.0f Q15*/, tmp );
+            Lscale = L_add( Mult_32_16( Lscale, tmp ), L_tmp1 );
+            L_tmp = Mult_32_16( Lscale, shaped_shb_excitation_fx[i] );                               /* Q_bwe_exc + (31-exp) - 15 */
+            shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
+            move16();
+        }
+    }
+    ELSE
+    {
+        FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+        {
+            tmp = round_fx_sat( L_shl( L_mult( 0x6666 /* 0.1 in Q12 */, shl( sub( i, 19 ), 11 ) ), 1 ) );
+            L_tmp1 = Mult_32_16( L_shl_o( 1, sub( 31, exp ), &Overflow ), tmp ); /* Q31-exp */
+            tmp = sub( 32767 /*1.0f Q15*/, tmp );
+            Lscale = L_add( Mult_32_16( Lscale, tmp ), L_tmp1 );
+            L_tmp = Mult_32_16( Lscale, shaped_shb_excitation_fx[i] );                               /* Q_bwe_exc + (31-exp) - 15 */
+            shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
+            move16();
+        }
+    }
+#else
     FOR( ; i < L_SHB_LAHEAD + 10; i++ )
     {
         tmp = i_mult_o( sub( i, 19 ), 3277 /*0.1f Q15*/, &Overflow );        /* Q15 */
@@ -2545,6 +2577,7 @@ void swb_tbe_enc_fx(
         shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
         move16();
     }
+#endif
 
     /* Update SHB excitation */
     Copy( shaped_shb_excitation_fx + L_FRAME16k, hBWE_TD->state_syn_shbexc_fx, L_SHB_LAHEAD ); /* Q_bwe_exc */
@@ -3831,6 +3864,38 @@ void swb_tbe_enc_ivas_fx(
             exp = 0;
             move16();
         }
+#ifdef FIX_ISSUE_1816_IMPROVE_MPY_ZERO_DOT_1_PRECISION
+        /*
+           code for EVS and IVAS are basically identical with the exception of i_mult_sat() which has precision issues
+           thus is was replaced for IVAS and kept for EVS, in order to keep EVS BE to test sequences and legacy implementations
+        */
+        IF( EQ_16( st_fx->element_mode, EVS_MONO ) )
+        {
+            FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+            {
+                tmp = i_mult_sat( sub( i, 19 ), 3277 /*0.1f Q15*/ );                 /* Q15 */
+                L_tmp1 = Mult_32_16( L_shl_o( 1, sub( 31, exp ), &Overflow ), tmp ); /* Q31-exp */
+                tmp = sub( 32767 /*1.0f Q15*/, tmp );
+                L_tmp = L_add( Mult_32_16( Lscale, tmp ), L_tmp1 );
+                L_tmp = Mult_32_16( L_tmp, shaped_shb_excitation_fx[i] );                                /* Q_bwe_exc + (31-exp) - 15 */
+                shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
+                move16();
+            }
+        }
+        ELSE
+        {
+            FOR( ; i < L_SHB_LAHEAD + 10; i++ )
+            {
+                tmp = round_fx_sat( L_shl( L_mult( 0x6666 /* 0.1 in Q12 */, shl( sub( i, 19 ), 11 ) ), 1 ) );
+                L_tmp1 = Mult_32_16( L_shl_o( 1, sub( 31, exp ), &Overflow ), tmp ); /* Q31-exp */
+                tmp = sub( 32767 /*1.0f Q15*/, tmp );
+                L_tmp = L_add( Mult_32_16( Lscale, tmp ), L_tmp1 );
+                L_tmp = Mult_32_16( L_tmp, shaped_shb_excitation_fx[i] );                                /* Q_bwe_exc + (31-exp) - 15 */
+                shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
+                move16();
+            }
+        }
+#else
         FOR( ; i < L_SHB_LAHEAD + 10; i++ )
         {
             tmp = i_mult_o( sub( i, 19 ), 3277 /*0.1f Q15*/, &Overflow );        /* Q15 */
@@ -3841,6 +3906,7 @@ void swb_tbe_enc_ivas_fx(
             shaped_shb_excitation_fx[i] = round_fx_o( L_shl_o( L_tmp, exp, &Overflow ), &Overflow ); /* Q_bwe_exc */
             move16();
         }
+#endif
     }
     ELSE
     {