diff --git a/lib_com/options.h b/lib_com/options.h
index 4653bb4604aff19c288a8072e0ca468ee55ba2ec..2b88deb5d39f9ae94fa912bfb6ff6033475c9488 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -67,6 +67,8 @@
 #define BASOP_NOGLOB_DECLARE_LOCAL
 #endif
 
+#define FIX_1378_ACELP_OUT_OF_BOUNDS
+
 /* Note: each compile switch (FIX_1101_...) is independent from the other ones */
 //#define OPT_STEREO_32KBPS_V1                    /* Optimization made in stereo decoding path for 32kbps decoding */
 #define OPT_AVOID_STATE_BUF_RESCALE             /* Optimization made to avoid rescale of synth state buffer */
diff --git a/lib_dec/dec_acelp_fx.c b/lib_dec/dec_acelp_fx.c
index 07750469f1515adef0f16688151631db8c2fef4b..51cbef624c6ea7d74e2a0b70cd7c4e6727ef2ba8 100644
--- a/lib_dec/dec_acelp_fx.c
+++ b/lib_dec/dec_acelp_fx.c
@@ -169,6 +169,7 @@ void D_ACELP_indexing_fx(
         pulses = pulsestrack[0];
         move16();
 
+#ifndef FIX_1378_ACELP_OUT_OF_BOUNDS
         /* safety check in case of bit errors */
         IF( GE_64( s, pulsestostates[16][pulses - 1] ) )
         {
@@ -177,9 +178,20 @@ void D_ACELP_indexing_fx(
             move16();
             return;
         }
+#endif
 
         IF( pulses )
         {
+#ifdef FIX_1378_ACELP_OUT_OF_BOUNDS
+            /* safety check in case of bit errors */
+            IF( GE_64( s, pulsestostates[16][pulses - 1] ) )
+            {
+                set16_fx( code, 0, L_SUBFR );
+                *BER_detect = 1;
+                move16();
+                return;
+            }
+#endif
             D_ACELP_decode_arithtrack_fx( code, s, pulses, num_tracks, 16 );
         }
         ELSE