diff --git a/lib_dec/ivas_stereo_mdct_core_dec_fx.c b/lib_dec/ivas_stereo_mdct_core_dec_fx.c
index cd7e92f71966fd4c7e001d16a6f27e9102980f6a..890e5fc9ef6db902a60454e094612449ceac424c 100644
--- a/lib_dec/ivas_stereo_mdct_core_dec_fx.c
+++ b/lib_dec/ivas_stereo_mdct_core_dec_fx.c
@@ -469,6 +469,14 @@ void stereo_mdct_core_dec_fx(
         move16();
         move16();
 
+        FOR( ch = 0; ch < CPE_CHANNELS; ch++ )
+        {
+            if ( NE_16( hCPE->hCoreCoder[ch]->core, TCX_20_CORE ) )
+            {
+                x_e[ch][1] = x_e[ch][0];
+                move16();
+            }
+        }
         stereo_decoder_tcx_fx( hCPE->hStereoMdct, ms_mask, x_0_fx[1], x_fx[0], x_fx[1], &hCPE->hStereoMdct->mdct_stereo_mode[0], sts[0]->core, sts[1]->core, sts[0]->igf, L_frameTCX[0], L_frameTCX[1], 0, sts[0]->last_core, sts[1]->last_core, 0, &q_x_1, &q_x_0 );
     }