diff --git a/lib_com/options.h b/lib_com/options.h
index 424110028debf7da0327fdb2c4881abb181d2567..819f2a42f0cad20d36fff06df04d7abdda08c2de 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -135,6 +135,7 @@
 #define NONBE_MDCT_ST_DTX_SKIP_DEWHITENING_OF_NOISE_SHAPES_ON_SID_FRAMES /* FhG: issue 1133: skip de-whitening of bg noise shape after frameloss period if the first good frame is an SID */
 #define NONBE_MDCT_ST_PLC_DO_NOT_SCALE_OLD_OUT_IF_FIRST_GOOD_IS_SID /* FhG: issue 1133: in TCX PLC, don't scale hHQ_core->old_out after applying fade to noise in burst frame error */
 #define NON_BE_FIX_BASOP_819_THRESHOLD_MASA2TOTAL
+#define FIX_903_ZERO_OUT_IMDCT_BUFFERS_FOR_MCT_IGNORE   /* FhG: zero out all relevant imdct buffers in MCT decoding of channels with mct_chan_mode == MCT_CHAN_MODE_IGNORE */
 
 /* ##################### End NON-BE switches ########################### */
 #define FIX_740_HQ_CORE_OVA // Proposed fix to solve overlap and add issue for HQ_CORE
diff --git a/lib_dec/ivas_mdct_core_dec.c b/lib_dec/ivas_mdct_core_dec.c
index 90cb85cc3b23d894503f6ba1b5b113912acc8afb..7201bad8cd2ada10041a2e406ba95e1c2bd40cd0 100644
--- a/lib_dec/ivas_mdct_core_dec.c
+++ b/lib_dec/ivas_mdct_core_dec.c
@@ -1862,6 +1862,15 @@ void ivas_mdct_core_reconstruct(
                 {
                     set_f( &synth[k * L_frame[ch]], 0.f, L_frame[ch] );
                     set_f( &synthFB[k * L_frame[ch]], 0.f, L_frameTCX[ch] );
+#ifdef FIX_903_ZERO_OUT_IMDCT_BUFFERS_FOR_MCT_IGNORE
+                    /* Note: these buffers are not subframe-based, hence no indexing with k */
+                    set_f( &st->hHQ_core->old_outLB[0], 0.f, L_frame[ch] );
+                    set_f( &st->hHQ_core->old_out[0], 0.f, L_frameTCX[ch] );
+                    set_f( &st->hTcxDec->syn_Overl[0], 0.f, L_frame[ch] / 2 );
+                    set_f( &st->hTcxDec->syn_OverlFB[0], 0.f, L_frameTCX[ch] / 2 );
+                    set_f( &st->hTcxDec->syn_Overl_TDAC[0], 0.f, L_frame[ch] / 2 );
+                    set_f( &st->hTcxDec->syn_Overl_TDACFB[0], 0.f, L_frameTCX[ch] / 2 );
+#endif
                 }
             }
 
@@ -2093,6 +2102,15 @@ void ivas_mdct_core_reconstruct_fx(
                 {
                     set16_fx( &synth_fx[k * L_frame[ch]], 0, L_frame[ch] );
                     set16_fx( &synthFB_fx[k * L_frame[ch]], 0, L_frameTCX[ch] );
+#ifdef FIX_903_ZERO_OUT_IMDCT_BUFFERS_FOR_MCT_IGNORE
+                    /* Note: these buffers are not subframe-based, hence no indexing with k */
+                    set16_fx( &st->hHQ_core->old_out_LB_fx[0], 0, L_frame[ch] );
+                    set16_fx( &st->hHQ_core->old_out_fx[0], 0, L_frameTCX[ch] );
+                    set16_fx( &st->hTcxDec->syn_Overl[0], 0, shr( L_frame[ch], 1 ) );
+                    set16_fx( &st->hTcxDec->syn_OverlFB[0], 0, shr( L_frameTCX[ch], 1 ) );
+                    set16_fx( &st->hTcxDec->syn_Overl_TDAC[0], 0, shr( L_frame[ch], 1 ) );
+                    set16_fx( &st->hTcxDec->syn_Overl_TDACFB[0], 0, shr( L_frameTCX[ch], 1 ) );
+#endif
                 }
             }