diff --git a/libavformat/utils.c b/libavformat/utils.c
index caf8df4ebd..d032baaf95 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -1932,7 +1932,7 @@ int av_find_stream_info(AVFormatContext *ic)
 //                if(st->codec->codec_type == CODEC_TYPE_VIDEO)
 //                    av_log(NULL, AV_LOG_ERROR, "%f\n", dur);
                 if(duration_count[index] < 2)
-                    memset(duration_error, 0, MAX_STREAMS * sizeof(*duration_error));
+                    memset(duration_error[index], 0, sizeof(*duration_error));
                 for(i=1; i<MAX_STD_TIMEBASES; i++){
                     int framerate= get_std_framerate(i);
                     int ticks= lrintf(dur*framerate/(1001*12));