diff --git a/lib_com/options.h b/lib_com/options.h
index 02e0476f5fddee21609243511fd9a22f9d7b5740..311624140804888cad46e84a22a7f70884db7ba3 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -87,6 +87,7 @@
 #define HARMONIZE_TBE2                                  /* VA: basop issue 2399: Remove duplicated code: TBE, step 2 */
 #define HARMONIZE_2427_GETPLC                           /* FhG: basop issue : 2427 Harmonizing getPLCDecision functions:*/
 #define HARM_FD_BWE                                     /* VA: harmonize core-coder FD BWE function duplications */
+#define FIX_2429_POST_DECODER
 #define FIX_FLOAT_1526_DIRAC_MEM_LEAK                   /* FhG: float issue 1526: potential memory leak in DirAC handles in case of format switching */
 #define FIX_2437_HARMONIZE_ENCODERINDEX                 /* FhG: basop issue 2437 EncoderIndex_ivas_fx() and EncoderIndex_fx()*/
 #define FIX_2385_GETTCXONLY                             /* FhG: issue 2385 : harmonizing getTcxonly_ivas_fx() and getTcxonly_ivas_fx() functions */
diff --git a/lib_com/prot_fx.h b/lib_com/prot_fx.h
index dd0315055eebd4ec7c13d02b6c5e95371af9b189..4845e22750999a2a2ff406803ddb65bc8ca263d7 100644
--- a/lib_com/prot_fx.h
+++ b/lib_com/prot_fx.h
@@ -7394,6 +7394,7 @@ Word16 FEC_pos_dec_fx(
     const Word16 nBits_es_Pred /* i  : number of bits for Es_pred Q                */
 );
 
+#ifndef FIX_2429_POST_DECODER
 void post_decoder(
     Decoder_State *st,
     Word16 synth_buf[],   /* Q0 */
@@ -7404,6 +7405,9 @@ void post_decoder(
 );
 
 void post_decoder_ivas_fx(
+#else
+void post_decoder_fx(
+#endif
     Decoder_State *st,
     Word16 synth_buf[],   // Q0
     Word16 pit_gain[],    // Q14
diff --git a/lib_dec/dec_LPD_fx.c b/lib_dec/dec_LPD_fx.c
index 0bc96a369d3551a2a9e869b5b34e8a8e4a82bbb6..d8eb395c56eb9e443b676283aaa43322a79fe372 100644
--- a/lib_dec/dec_LPD_fx.c
+++ b/lib_dec/dec_LPD_fx.c
@@ -954,7 +954,11 @@ void decoder_LPD_fx(
     st->last_is_cng = 0;
 
     /* Postfiltering */
+#ifdef FIX_2429_POST_DECODER
+    post_decoder_fx( st, synth_buf, pit_gain, pitch, signal_out, bpf_noise_buf );
+#else
     post_decoder( st, synth_buf, pit_gain, pitch, signal_out, bpf_noise_buf );
+#endif
 
     IF( signal_outFB )
     {
diff --git a/lib_dec/ivas_mdct_core_dec_fx.c b/lib_dec/ivas_mdct_core_dec_fx.c
index 07fb3593eb021bf09dcd893941b37b61add58974..39694bdcb070a65abea97a6d0d805fd6c01fc26b 100644
--- a/lib_dec/ivas_mdct_core_dec_fx.c
+++ b/lib_dec/ivas_mdct_core_dec_fx.c
@@ -1402,7 +1402,11 @@ void ivas_mdct_core_reconstruct_fx(
             Copy_Scale_sig_32_16( st->p_bpf_noise_buf_32, st->p_bpf_noise_buf, st->L_frame, -Q11 ); // Q11 -> Q0
         }
 
+#ifdef FIX_2429_POST_DECODER
+        post_decoder_fx( st, synth_buf_fx, pit_gain_fx[ch], pitch[ch], x_fx_16, st->p_bpf_noise_buf );
+#else
         post_decoder_ivas_fx( st, synth_buf_fx, pit_gain_fx[ch], pitch[ch], x_fx_16, st->p_bpf_noise_buf );
+#endif
 
         IF( st->p_bpf_noise_buf_32 )
         {
diff --git a/lib_dec/ivas_tcx_core_dec_fx.c b/lib_dec/ivas_tcx_core_dec_fx.c
index c3d9b2911f756467f4bd2b2b560cb2ddd038d551..19025b4031211ea9deb377bd6e50a69153a46cfb 100644
--- a/lib_dec/ivas_tcx_core_dec_fx.c
+++ b/lib_dec/ivas_tcx_core_dec_fx.c
@@ -788,7 +788,11 @@ void stereo_tcx_core_dec_fx(
 
     /* Postfiltering */
 
+#ifdef FIX_2429_POST_DECODER
+    post_decoder_fx( st, synth_buf_fx, pit_gain_fx, pitch, signal_out_fx, st->p_bpf_noise_buf );
+#else
     post_decoder( st, synth_buf_fx, pit_gain_fx, pitch, signal_out_fx, st->p_bpf_noise_buf );
+#endif
 
     test();
     IF( st->p_bpf_noise_buf_32 && st->tcxonly == 0 )
diff --git a/lib_dec/post_dec_fx.c b/lib_dec/post_dec_fx.c
index 8bf9380b3fbe89ad809c452874a919b35cb61be8..6d89900c27b9befc3db9f145960430be1d71e1b2 100644
--- a/lib_dec/post_dec_fx.c
+++ b/lib_dec/post_dec_fx.c
@@ -20,6 +20,7 @@ static void bass_pf_1sf_delay( Word16 *syn, Word16 *T_sf, Word16 *gainT_sf, Word
  * Perform post-processing
  *---------------------------------------------------------------------*/
 
+#ifndef FIX_2429_POST_DECODER
 void post_decoder(
     Decoder_State *st,
     Word16 synth_buf[],   /* Q0 */
@@ -173,6 +174,9 @@ void post_decoder(
 
 
 void post_decoder_ivas_fx(
+#else
+void post_decoder_fx(
+#endif
     Decoder_State *st,
     Word16 synth_buf[],   // Q0
     Word16 pit_gain[],    // Q14
@@ -234,11 +238,29 @@ void post_decoder_ivas_fx(
         IF( pfstat_on_previous )
         {
             Copy( st->hPFstat->mem_pf_in + L_SYN_MEM - M, synth - M, M );
+#ifdef FIX_2429_POST_DECODER
+            IF( EQ_16( st->element_mode, EVS_MONO ) )
+            {
+                Residu3_fx( st->old_Aq_12_8_fx, synth, synth_buf, L_SUBFR, 1 );
+                E_UTIL_synthesis( 1, st->old_Aq_12_8_fx, synth_buf, synth2, L_SUBFR, st->hPFstat->mem_stp + L_SYN_MEM - M, 0, M );
+                scale_st_fx( synth, synth2, &st->hPFstat->gain_prec, L_SUBFR );
+                blend_subfr2_fx( synth2 + L_SUBFR / 2, synth + L_SUBFR / 2, synth2 + L_SUBFR / 2 );
+            }
+            ELSE
+            {
+                Word16 L_subfr = idiv1616( st->L_frame, st->nb_subfr );
+                Residu3_fx( st->old_Aq_12_8_fx, synth, synth_buf, L_subfr, 1 );
+                E_UTIL_synthesis( 1, st->old_Aq_12_8_fx, synth_buf, synth2, L_subfr, st->hPFstat->mem_stp + L_SYN_MEM - M, 0, M );
+                scale_st_fx( synth, synth2, &st->hPFstat->gain_prec, L_subfr );
+                blend_subfr2_fx( synth2 + shr( L_subfr, 1 ), synth + shr( L_subfr, 1 ), synth2 + shr( L_subfr, 1 ) );
+            }
+#else
             Word16 L_subfr = idiv1616( st->L_frame, st->nb_subfr );
             Residu3_fx( st->old_Aq_12_8_fx, synth, synth_buf, L_subfr, 1 );
             E_UTIL_synthesis( 1, st->old_Aq_12_8_fx, synth_buf, synth2, L_subfr, st->hPFstat->mem_stp + L_SYN_MEM - M, 0, M );
             scale_st_fx( synth, synth2, &st->hPFstat->gain_prec, L_subfr );
             blend_subfr2_fx( synth2 + shr( L_subfr, 1 ), synth + shr( L_subfr, 1 ), synth2 + shr( L_subfr, 1 ) );
+#endif
         }
     }
     ELSE
diff --git a/lib_dec/updt_dec_fx.c b/lib_dec/updt_dec_fx.c
index 27983b42e469050c699741b2e31c1c0e20c55090..6130388759319652b214f977909e0af69db4215a 100644
--- a/lib_dec/updt_dec_fx.c
+++ b/lib_dec/updt_dec_fx.c
@@ -1028,7 +1028,11 @@ void update_decoder_LPD_cng(
     st->bpf_gain_param = 0;
     move16();
 
+#ifdef FIX_2429_POST_DECODER
+    post_decoder_fx( st, buf_synth, pf_gain, pf_pitch, timeDomainBuffer, bpf_noise_buf );
+#else
     post_decoder( st, buf_synth, pf_gain, pf_pitch, timeDomainBuffer, bpf_noise_buf );
+#endif
 
     return;
 }