[MPlayer-dev-eng] Video lags behind audio a bit when using libmad for mp3 decoding

[Siarhei Siamashka]

Using -ac mad, video and audio are out of sync a bit. This lag can be observed
with very low audio bitrate (32kbps). The problem is in ad_libmad.c:48
  sh->audio_in_minsize=4096;

When increasing sh->audio_in_minsize value, the lag becomes much larger and
much easier to notice. So probably decreasing this value should reduce lag as
well. I wonder what value is safe? Probably that's the largest valid mp3 audio
frame size?