diff --git a/lib_com/options.h b/lib_com/options.h
index 7ac8448cf859d4c8c9bd5c73ea047e21be10c514..f8de808c1a4c8162b4e6a6cb94c9b240eec0e6d0 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -162,6 +162,7 @@
 #define FIX_522_ISM_FIRST_SID                           /* VA: fix ISM decoder crash if first received frame is an SID */
 #define FIX_470_MASA_JBM_EXT                            /* Nokia: Issue 470, fix MASA EXT output with JBM */
 #define ISM_FB                                          /* issue 556: change SWB to FB coding in 1ISM at 24.4 kbps */
+#define FIX_558_PLC_DISCONT                             /* FhG: issue 558: fix discontinuities in DFT Stereo when switching from TCX concealment to ACELP */
 
 
 /* ################## End DEVELOPMENT switches ######################### */
diff --git a/lib_dec/ivas_post_proc.c b/lib_dec/ivas_post_proc.c
old mode 100644
new mode 100755
index 0321a646f95b7ccd8157a9398d3ee7a949914734..7f1c84983b3834b6948e06c0af71cd88341cc0d0
--- a/lib_dec/ivas_post_proc.c
+++ b/lib_dec/ivas_post_proc.c
@@ -208,7 +208,11 @@ void stereo_dft_dec_core_switching(
         lerp( hCPE->input_mem_BPF[0], hCPE->input_mem_BPF[0], NS2SA( st->L_frame * FRAMES_PER_SEC, STEREO_DFT32MS_OVL_NS ), NS2SA( st->last_L_frame * FRAMES_PER_SEC, STEREO_DFT32MS_OVL_NS ) );
     }
 
+#ifdef FIX_558_PLC_DISCONT
+    if ( st->prev_bfi && !( st->last_core_bfi == ACELP_CORE && st->last_con_tcx == 1 ) )
+#else
     if ( st->prev_bfi )
+#endif
     {
         /* last_core needed for correctly decoding ACELP->TCX/HQ switching frames in ivas_core_dec().
            In the following steps the decoder needs to consider if the core was changed due to a lost frame to apply the correct transition */
@@ -414,6 +418,7 @@ void stereo_dft_dec_core_switching(
             {
                 lerp( hCPE->input_mem[0], hCPE->input_mem_LB[0], NS2SA( st->L_frame * FRAMES_PER_SEC, STEREO_DFT32MS_OVL_NS ), NS2SA( output_frame * FRAMES_PER_SEC, STEREO_DFT32MS_OVL_NS ) );
             }
+
             /* ACELP synthesis @ internal sampling rate */
             stereo_dft_dec_analyze( hCPE, output, DFT, 0, st->L_frame, output_frame, DFT_STEREO_DEC_ANA_LB, 0, 0 );
 
@@ -436,6 +441,7 @@ void stereo_dft_dec_core_switching(
     }
 #endif
 
+
     /*----------------------------------------------------------------*
      * enhanced stereo filling: allpass filter
      *----------------------------------------------------------------*/