diff --git a/lib_com/cng_exc_fx.c b/lib_com/cng_exc_fx.c
index 42802ee152657a498613e2801bd14d9b6f1226af..084f28796f11101d73d7789a7972e75e36b03651 100644
--- a/lib_com/cng_exc_fx.c
+++ b/lib_com/cng_exc_fx.c
@@ -872,7 +872,11 @@ void cng_params_upd_fx(
             Word16 index = 0;
             move32();
             move16();
+#ifdef HARM_2456_APPLY_SCALE
+            index = apply_scale_ind( &att_fx, bwidth, last_active_brate, scaleTableStereo, SIZE_SCALE_TABLE_STEREO );
+#else
             apply_scale_ivas_fx( &att_fx, bwidth, last_active_brate, scaleTableStereo, SIZE_SCALE_TABLE_STEREO, &index );
+#endif
             att_fx = pow_10_q23[index]; // Q23
             move32();
             tmp = extract_h( att_fx ); // Q7
diff --git a/lib_com/fd_cng_com_fx.c b/lib_com/fd_cng_com_fx.c
index f7b58ae6256c1f34a0a6fde9f0e94886369dd540..0a1fe1d3287ee24cb325e1eae7a65acee2c82841 100644
--- a/lib_com/fd_cng_com_fx.c
+++ b/lib_com/fd_cng_com_fx.c
@@ -1751,9 +1751,11 @@ Word16 apply_scale_ind(
         *scale = L_add( *scale, L_deposit_h( scaleTable[i].scale ) );
         move32();
     }
+
     return i;
 }
 
+#ifndef HARM_2456_APPLY_SCALE
 void apply_scale_ivas_fx(
     Word32 *scale,                 /* o  : scalefactor             */
     const Word16 bwmode,           /* i  : audio bandwidth         */
@@ -1780,6 +1782,7 @@ void apply_scale_ivas_fx(
     *index = i;
     move16();
 }
+#endif
 /*-------------------------------------------------------------------
  * bandcombinepow()
  *
diff --git a/lib_com/options.h b/lib_com/options.h
index b207c8345cf4fbbb1512c38dd208dd0ad1b8e58f..8b6b40f990c1cfc91d230b1e5b02713c95edf160 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -101,6 +101,7 @@
 #define HARMONIZE_TBE3                                  /* VA: basop issue 2399: Remove duplicated code: TBE, step 3 */
 #define FIX_2459_USAN_AMR_SIDSTART                      /* FhG: basop issue 2459: fix msan complaint */
 #define FIX_2458_USAN_NULLPTR_WITH_ZERO_OFFSET          /* FhG: basop issue 2458: avoid indexing into null pointer */
+#define HARM_2456_APPLY_SCALE                           /* FhG basop issue 2456: Harmonize apply_scale_ind(), apply_scale_ivas_fx() */
 
 /* #################### End BE switches ################################## */
 
diff --git a/lib_com/prot_fx.h b/lib_com/prot_fx.h
index 068770b1c6720fbe43942109b1e61da8a00486cf..8f41d4871348d5726f07ca490e060c95110d50a1 100644
--- a/lib_com/prot_fx.h
+++ b/lib_com/prot_fx.h
@@ -4884,6 +4884,7 @@ Word16 apply_scale_ind(
     const SCALE_SETUP *scaleTable, /* i  : Scale table             */
     const Word16 scaleTableSize    /* i  : Size of scale table     */
 );
+#ifndef HARM_2456_APPLY_SCALE
 void apply_scale_ivas_fx(
     Word32 *scale,                 /* o  : scalefactor             */
     const Word16 bwmode,           /* i  : audio bandwidth         */
@@ -4891,6 +4892,7 @@ void apply_scale_ivas_fx(
     const SCALE_SETUP *scaleTable, /* i  : Scale table             */
     const Word16 scaleTableSize,   /* i  : Size of scale table     */
     Word16 *index );
+#endif
 
 /* Compute the power for each partition */
 void bandcombinepow(
diff --git a/lib_enc/cng_enc_fx.c b/lib_enc/cng_enc_fx.c
index e76a227ae6774b7fb23e6a8e5044eebd28c9ae63..0d6de1ed5a36991bb3ac3b9f2793a5a773703656 100644
--- a/lib_enc/cng_enc_fx.c
+++ b/lib_enc/cng_enc_fx.c
@@ -1679,9 +1679,14 @@ static Word16 shb_DTX_fx(
     {
         Word32 att_fx32 = 0;
         move32();
+#ifdef HARM_2456_APPLY_SCALE
+
+        apply_scale( &att_fx32, st->hFdCngEnc->hFdCngCom->CngBandwidth, st->hFdCngEnc->hFdCngCom->CngBitrate, scaleTableStereo, SIZE_SCALE_TABLE_STEREO ); // Q23;
+#else
         Word16 index;
 
         apply_scale_ivas_fx( &att_fx32, st->hFdCngEnc->hFdCngCom->CngBandwidth, st->hFdCngEnc->hFdCngCom->CngBitrate, scaleTableStereo, SIZE_SCALE_TABLE_STEREO, &index ); // Q23;
+#endif
 
         att_fx = extract_l( L_shr( att_fx32, 15 ) ); // Q8
     }