diff --git a/lib_com/options.h b/lib_com/options.h
index cf016659dadd0463a03c3b7f1af8f921df038de5..7872de13b305e2d78690a1d335f4f5ca8b96cf31 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -165,6 +165,7 @@
 #define FIX_1835_REVERB_ACTIVATION                      /* FhG: Modified reverberation activation logic and corrected factEQ calculation */
 #define NON_BE_FIX_EVS_USAN_ERR_IN_WAVEADJUST           /* FhG: address issue 1037 */
 #define FIX_1038_OFFSET_TO_NULL_PTR_IN_EVS_TCX_BFI      /* FhG: move setting of pointers for parameter decoding so they are skipped in lost frames when they are not needed */
+#define NONBE_FIX_1056_ISM_RATE_SWITCH                  /* FhG: Fix #1056: fix TC buffer udpate on a ISM rate switch */	
 
 /* #################### End BASOP porting switches ############################ */
 
diff --git a/lib_dec/ivas_ism_dec_fx.c b/lib_dec/ivas_ism_dec_fx.c
index 41c1efcdc6889c15f86b8c64419cf958c106b0e4..ec5a19a5db5a11e7aa94b69da1cfc055b757741b 100644
--- a/lib_dec/ivas_ism_dec_fx.c
+++ b/lib_dec/ivas_ism_dec_fx.c
@@ -142,9 +142,16 @@ static ivas_error ivas_ism_bitrate_switching_dec_fx(
     {
         test();
         test();
+#ifndef NONBE_FIX_1056_ISM_RATE_SWITCH
         test();
-        /* transfer subframe info from DirAC or ParamMC to central tc buffer */
+#endif
+/* transfer subframe info from DirAC or ParamMC to central tc buffer */
+#ifdef NONBE_FIX_1056_ISM_RATE_SWITCH
+        /* only do this if we are not having done everything already in the TC decoding part and having only played out from the TC buffer */
+        IF( EQ_32( last_ism_mode, ISM_MODE_PARAM ) && st_ivas->hSpatParamRendCom != NULL && NE_32( st_ivas->hTcBuffer->tc_buffer_mode, TC_BUFFER_MODE_BUFFER ) )
+#else
         IF( EQ_32( last_ism_mode, ISM_MODE_PARAM ) && st_ivas->hSpatParamRendCom != NULL && ( NE_32( st_ivas->renderer_type, RENDERER_MONO_DOWNMIX ) && NE_32( st_ivas->renderer_type, RENDERER_DISABLE ) ) )
+#endif
         {
             st_ivas->hTcBuffer->nb_subframes = st_ivas->hSpatParamRendCom->nb_subframes;
             move16();
diff --git a/lib_dec/ivas_jbm_dec_fx.c b/lib_dec/ivas_jbm_dec_fx.c
index 48264d70fb7cb3dd87229a603e510fa7d4c1a798..f4c6619508cf5082146d692d26f56fc836d35b39 100644
--- a/lib_dec/ivas_jbm_dec_fx.c
+++ b/lib_dec/ivas_jbm_dec_fx.c
@@ -3828,6 +3828,9 @@ static void ivas_jbm_dec_tc_buffer_playout_fx(
         slots_to_render = sub( slots_to_render, st_ivas->hTcBuffer->subframe_nbslots[last_sf] );
         last_sf = add( last_sf, 1 );
     }
+#ifdef DEBUGGING
+    assert( slots_to_render == 0 );
+#endif
 
     FOR( ch_idx = 0; ch_idx < st_ivas->hTcBuffer->nchan_transport_jbm; ch_idx++ )
     {