diff --git a/lib_com/options.h b/lib_com/options.h
old mode 100644
new mode 100755
index 964bcd18b4afb7544d18b7c7790566b42fdb9ed1..a47754e10376fdd01b036d31e8728430d9d0d6c4
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -158,6 +158,7 @@
 #define FIX_955_FASTCONV_REND_IN_ISM                    /* VA: put FastConv rendering call under DEBUGGING */
 #define FIX_969_USAN_IGF_ARITH                          /* FhG: issue 969: fix USAN error in igf_sce_dec; same issue as #962 */
 #define FIX_959_MASA_LINEAR_REND                        /* VA: issue 959: remove unused calling of ivas_sba_linear_renderer() in MASA rendering */
+#define FIX_963_USAN_ERROR                              /* Eri: Issue 963: USAN error in Stereo CNG, division by zero */
 #define FIX_971_LOG2_IDX_GAIN_0                         /* VA: prevent -Inf due to log2(ratio==0) */
 
 /* #################### End BE switches ################################## */
diff --git a/lib_enc/ivas_stereo_dft_enc_itd.c b/lib_enc/ivas_stereo_dft_enc_itd.c
index d3336f4eb604e5fba2dd1ede2fe9de49ec870dfc..13b72ea7b956becbf02edecb58d7dccfcfffdcbc 100755
--- a/lib_enc/ivas_stereo_dft_enc_itd.c
+++ b/lib_enc/ivas_stereo_dft_enc_itd.c
@@ -908,7 +908,18 @@ void stereo_dft_enc_compute_itd(
                 {
                     hStereoDft->expectedNumUpdates += 1 + min( hCPE->hFrontVad[0]->rem_dtx_ho, hCPE->hFrontVad[1]->rem_dtx_ho );
                 }
+#ifdef FIX_963_USAN_ERROR
+                if ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates == 0 )
+                {
+                    cng_xcorr_filt = max( CORR_FILT, sfm_L );
+                }
+                else
+                {
+                    cng_xcorr_filt = max( min( CORR_FILT, 10.0f * CORR_FILT / ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates ) ), sfm_L );
+                }
+#else
                 cng_xcorr_filt = max( min( CORR_FILT, 10.0f * CORR_FILT / ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates ) ), sfm_L );
+#endif
                 hStereoDft->currentNumUpdates++;
                 for ( i = 1; i < NFFT / 2; i++ )
                 {
@@ -943,7 +954,18 @@ void stereo_dft_enc_compute_itd(
             if ( vad_flag_dtx[0] == 0 )
             {
                 /* expectedNumUpdates updated after call to dtx() in SID frames */
+#ifdef FIX_963_USAN_ERROR
+                if ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates == 0 )
+                {
+                    cng_xcorr_filt = max( CORR_FILT, sfm_L );
+                }
+                else
+                {
+                    cng_xcorr_filt = max( min( CORR_FILT, 10.0f * CORR_FILT / ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates ) ), sfm_L );
+                }
+#else
                 cng_xcorr_filt = max( min( CORR_FILT, 10.0f * CORR_FILT / ( hStereoDft->expectedNumUpdates + hStereoDft->currentNumUpdates ) ), sfm_L );
+#endif
                 hStereoDft->currentNumUpdates++;
                 hStereoDft->sfm = cng_xcorr_filt;
             }