diff --git a/lib_com/options.h b/lib_com/options.h
index 4527c9c4b1d733e77e82986c675b0b267b74cdc1..79443ece86b896cefc0f98f9e6585e26c31add97 100755
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -128,6 +128,8 @@
 #define FIX_998_UNUSED_FUNCTION                         /* FhG: issue 998: delete unused funtion ivas_dirac_dec_get_response_split_order */ 
 #define NONBE_FIX_1014_1015_1016_OSBA_JBM_STEREO              /* FhG: issues #1014, #1015, #1016: fix tc buffer info update in the discrete ism renderer */
 #define NONBE_FIX_987_PARAMC_BINAURAL_REVERB_RENDERING       /* FhG: issue 987: solution b: downmix HOA3 to stereo a input for the reverberator */
+#define NONBE_FIX_1006_PAST_DMX_NRG_ERROR               /* Eri/FhG: Issue 1006: Bug fix in ivas_stereo_dft_dec not replicated in ivas_stereo_dft_dec_dmx */
+
 
 /* #################### End BASOP porting switches ############################ */
 
diff --git a/lib_dec/ivas_stereo_dft_dec_dmx_fx.c b/lib_dec/ivas_stereo_dft_dec_dmx_fx.c
index cdb64e46c62c5c73343b11c8a202d9623923088b..59ee077e8750f6ffa703550d4c583948bba0cbf9 100644
--- a/lib_dec/ivas_stereo_dft_dec_dmx_fx.c
+++ b/lib_dec/ivas_stereo_dft_dec_dmx_fx.c
@@ -378,10 +378,15 @@ void stereo_dft_unify_dmx_fx(
             Word16 idx_k0, idx_k1;
             Word16 q_shift0;
             Word16 q_shift1;
+#ifdef NONBE_FIX_1006_PAST_DMX_NRG_ERROR
+            idx_k0 = add( hStereoDft->past_DMX_pos, STEREO_DFT_PAST_MAX - 1 ) & ( STEREO_DFT_PAST_MAX - 1 ); /* Q0 */
+            idx_k1 = add( idx_k0, 1 ) & ( STEREO_DFT_PAST_MAX - 1 );
+#else
             idx_k0 = ( add( hStereoDft->past_DMX_pos, 1 ) ) % STEREO_DFT_PAST_MAX;
             move16();
             idx_k1 = ( add( idx_k0, 1 ) ) % STEREO_DFT_PAST_MAX;
             move16();
+#endif
             q_shift0 = sub( hStereoDft->q_dft, hStereoDft->q_DFT_past_DMX_fx[idx_k0] );
             q_shift1 = sub( hStereoDft->q_dft, hStereoDft->q_DFT_past_DMX_fx[idx_k1] );