diff --git a/libmpdemux/demux_audio.c b/libmpdemux/demux_audio.c
index 0370ec7591..802d36eacc 100644
--- a/libmpdemux/demux_audio.c
+++ b/libmpdemux/demux_audio.c
@@ -790,7 +790,8 @@ static void demux_close_audio(demuxer_t* demuxer) {
 
 static int demux_audio_control(demuxer_t *demuxer,int cmd, void *arg){
     sh_audio_t *sh_audio=demuxer->audio->sh;
-    int audio_length = sh_audio->i_bps ? demuxer->movi_end / sh_audio->i_bps : 0;
+    int audio_length = sh_audio->i_bps && demuxer->movi_end > demuxer->movi_start ?
+                       (demuxer->movi_end - demuxer->movi_start) / sh_audio->i_bps : 0;
     da_priv_t* priv = demuxer->priv;
 
     switch(cmd) {