diff --git a/lib_com/options.h b/lib_com/options.h
index 1926ef74201502e790a43d7f19ec969a456a7c64..360d78423bbe58b749546024c29d8bfdaef22895 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -123,6 +123,7 @@
 //#define FIX_777_COMBI_RENDER_CONFIG_FILE                /* Philips: Fix for combined renderer config file support */
 /* #define NONBE_FIX_991_PARAMBIN_BINARY_HRTF   */           /* Nokia: issue #991: fix using of binary file HRTF in ParamBin (to activate when USE_NEW_HRTF_BINARY_FILE_FORMAT and FIX_777_COMBI_RENDER_CONFIG_FILE are on ) */
 
+#define FIX_1024_REMOVE_PARAMMC_MIXING_MAT              /* VA: issue 1024: remove unused function ivas_param_mc_get_mono_stereo_mixing_matrices() */
 
 /* #################### End BASOP porting switches ############################ */
 
diff --git a/lib_dec/ivas_mc_param_dec_fx.c b/lib_dec/ivas_mc_param_dec_fx.c
index 1ee6d6cede436d386749f86de10f924c6b62ab3f..1767f5cdebc250b5c0f9080794905ac8f876b408 100644
--- a/lib_dec/ivas_mc_param_dec_fx.c
+++ b/lib_dec/ivas_mc_param_dec_fx.c
@@ -3063,6 +3063,7 @@ static void ivas_param_mc_get_mixing_matrices_fx(
     return;
 }
 
+#ifndef FIX_1024_REMOVE_PARAMMC_MIXING_MAT
 
 /*-------------------------------------------------------------------------
  * ivas_param_mc_get_mono_stereo_mixing_matrices()
@@ -3071,6 +3072,7 @@ static void ivas_param_mc_get_mixing_matrices_fx(
  * for mono and stereo output
  *------------------------------------------------------------------------*/
 
+#endif
 
 /*-------------------------------------------------------------------------
  * param_mc_update_mixing_matrices()
diff --git a/lib_dec/ivas_out_setup_conversion_fx.c b/lib_dec/ivas_out_setup_conversion_fx.c
index 93a7c204e891f5b88d5519612e7a876a70a2a320..5ce1f08f1adbd7b003371f84cfb778447a258627 100644
--- a/lib_dec/ivas_out_setup_conversion_fx.c
+++ b/lib_dec/ivas_out_setup_conversion_fx.c
@@ -1190,7 +1190,11 @@ void ivas_ls_setup_conversion_process_mdct_param_mc_fx(
         set_zero_fx( cy_fx, MAX_CICP_CHANNELS * MAX_CICP_CHANNELS );
         set_zero_fx( Nrqq_fx, MAX_OUTPUT_CHANNELS );
         set_zero_fx( target_ch_ener_fx, MAX_OUTPUT_CHANNELS );
+#ifdef FIX_1024_REMOVE_PARAMMC_MIXING_MAT
+        /* Step 1.2, get target channel energies for the transported format, Nrqq calculation */
+#else
         /* Step 1.2, get target channel energies for the transported format as in ivas_param_mc_get_mono_stereo_mixing_matrices(), Nrqq calculation */
+#endif
         ild_q_fx = hParamMC->icld_q_fx + imult1616( bandIdx, hParamMC->hMetadataPMC->ild_mapping_conf->ild_map_size_lfe );
         move16();
         FOR( chInIdx = 0; chInIdx < nchan_transport_format; chInIdx++ )
@@ -1212,7 +1216,11 @@ void ivas_ls_setup_conversion_process_mdct_param_mc_fx(
             move32();
         }
 
+#ifdef FIX_1024_REMOVE_PARAMMC_MIXING_MAT
+        /* Step 1.3 get target Cy () (with dmx matrix from CICPX to MONO/STEREO saved in hParamMC) */
+#else
         /* Step 1.3 get target Cy like in ivas_param_mc_get_mono_stereo_mixing_matrices() (with dmx matrix from CICPX to MONO/STEREO saved in hParamMC) */
+#endif
         FOR( chOutIdx = 0; chOutIdx < nchan_out; chOutIdx++ )
         {
             FOR( i = 0; i < nchan_transport_format; i++ )