diff --git a/libavcodec/aacenc.c b/libavcodec/aacenc.c
index dd8a83c53710e..eae933235fc37 100644
--- a/libavcodec/aacenc.c
+++ b/libavcodec/aacenc.c
@@ -364,7 +364,7 @@ static void adjust_frame_information(AACEncContext *apc, ChannelElement *cpe, in
         if (msc == 0 || ics0->max_sfb == 0)
             cpe->ms_mode = 0;
         else
-            cpe->ms_mode = msc < ics0->max_sfb ? 1 : 2;
+            cpe->ms_mode = msc < ics0->max_sfb * ics0->num_windows ? 1 : 2;
     }
 }