diff --git a/lib_com/options.h b/lib_com/options.h
index b27b5da4c3e31b39f5baa95fc8ffc2c1b225b493..7976d55ed38872eaff721d16b919104efaa9a040 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -102,6 +102,7 @@
 #define FIX_2488_PREVENT_NEG_PITCH                      /* VA: Fix for 2488, use saturation to prevent possible wrap-around, thus negative pitch values */
 #define FIX_1547_ISMDTX_HANDLE                          /* VA: float issue 1547: fix use of 'hISMDTX' handle */
 #define FIX_1540_EXPOSE_PT_IN_RTP_HEADER_API            /* Expose Payload Type setting in RTP Header */
+#define FIX_BASOP_2491_MDCT_JBM_CLICK                   /* FhG: BASOP #2491: Fix Q_synth after TCX concealment (using ACELP concealment) */
 
 /* ##################### End NON-BE switches ########################### */
 
diff --git a/lib_dec/er_dec_tcx_fx.c b/lib_dec/er_dec_tcx_fx.c
index 0eecfedee5ce85c5cb02452fb4e690b4c1de224e..867ecda5137846437287f8a02a960409c6fdc9d5 100644
--- a/lib_dec/er_dec_tcx_fx.c
+++ b/lib_dec/er_dec_tcx_fx.c
@@ -941,6 +941,9 @@ void con_tcx_fx(
     }
     ELSE
     {
+#ifdef FIX_BASOP_2491_MDCT_JBM_CLICK
+        tmp_deemph = shl_sat( tmp_deemph, Q_syn ); /*Q_syn*/
+#else
         IF( NE_16( st->element_mode, EVS_MONO ) ) // to keep evs bit-exactness
         {
             if ( GT_16( sub( Q_syn, st->Q_syn_factor ), scf ) )
@@ -953,6 +956,7 @@ void con_tcx_fx(
         {
             tmp_deemph = shl_sat( tmp_deemph, Q_syn ); /*Q_syn*/
         }
+#endif
         st->Q_syn_factor = 0;
         move16();
         st->Q_syn = Q_syn;
diff --git a/lib_dec/ivas_core_dec_fx.c b/lib_dec/ivas_core_dec_fx.c
index 40688cf919ed9544c4e9b96ec261e00e53621a91..56e283a3be98c2249b3edb965426938f96bd7723 100644
--- a/lib_dec/ivas_core_dec_fx.c
+++ b/lib_dec/ivas_core_dec_fx.c
@@ -766,7 +766,18 @@ ivas_error ivas_core_dec_fx(
          *---------------------------------------------------------------------*/
 
         /*core_switching_post_dec*/
+#ifdef FIX_BASOP_2491_MDCT_JBM_CLICK
+        IF( EQ_16( sts[n]->element_mode, IVAS_CPE_MDCT ) && GT_32( sts[n]->core_brate, SID_2k40 ) ) // In this case, st->Q_syn_factor was already applied earlier in ivas_mdct_core_reconstruct_fx()
+        {
+            Q_synth = sub( 15, e_sig[0] );
+        }
+        ELSE
+        {
+            Q_synth = add( sub( 15, e_sig[0] ), st->Q_syn_factor );
+        }
+#else
         Q_synth = add( sub( 15, e_sig[0] ), st->Q_syn_factor );
+#endif
 
         IF( st->cldfbSyn != NULL )
         {
diff --git a/lib_dec/stat_dec.h b/lib_dec/stat_dec.h
index bec9811e984287a4c37ae8aec1e14ddc43d3d2a0..58056843eb6fc00397370916450dd4c7d3b2be26 100644
--- a/lib_dec/stat_dec.h
+++ b/lib_dec/stat_dec.h
@@ -1306,7 +1306,7 @@ typedef struct Decoder_State
     Word16 Q_syn;
     Word16 Q_syn2;
     Word16 Q_syn_cng;
-    Word16 Q_syn_factor; // This q_factor is used to avoid using fix Q0 for synth[] at the output of con_tcx_ivas_fx() and ivas_core_dec_fx(). For con_tcx_ivas_fx, it is used for two consecutive TCX concealment processes and It cannot be greater than 0.
+    Word16 Q_syn_factor; // This q_factor is used to avoid using fix Q0 for synth[] at the output of con_tcx_fx() and ivas_core_dec_fx(). For con_tcx_fx, it is used for two consecutive TCX concealment processes and It cannot be greater than 0.
     Word16 prev_Q_syn;
     Word16 prev_Q_bwe_exc;