diff --git a/lib_dec/ivas_ism_dtx_dec.c b/lib_dec/ivas_ism_dtx_dec.c
index 7eb6c115ea3d7b28c6c3952f0f2b9c8701113c39..935db95eea5708afbf995aaa599ac212607d1094 100644
--- a/lib_dec/ivas_ism_dtx_dec.c
+++ b/lib_dec/ivas_ism_dtx_dec.c
@@ -190,6 +190,7 @@ ivas_error ivas_ism_dtx_dec(
             st->bit_stream = st_ivas->hSCE[0]->hCoreCoder[0]->bit_stream;
             st->next_bit_pos = 0; /* note: needed in paramISM -> discISM switching */
             st->cng_ism_flag = 1;
+            st->L_frame = min( st->L_frame, L_FRAME16k ); /* note: needed for switching from active frame with L_frame=640 to CNG in object with no SID */
 #else
             ivas_ism_preprocessing( st_ivas, ch ); // VE: after the acceptance of switches, replace the function call by its content
 #endif