It is a shame: we have some DVD videos that are played correctly by some Windows dvd players, but Mplayer cannot play the audio stream on them.

The error reported by mplayer is: "Too many video packets ... in the buffer"

The error is the same using Mplayer 0.92 on a Debian-based distro and Mplayer 1.05pre (installed from packman package) on SuSE 9.1 machines, too.

One of the DVDs not played by mplayer correctly has two AC3 audio streams: the en stream is played OK, but the hu stream results in the above-mentioned error.

The mplayer faq suggests using the -ni and -framedrop options, but those did not help.
It also mentions that this error may be present on slow systems, but we got this error on rather fast systems with Celeron 1.7G and above.

DVD region code matters should not be an issue, as these are DVDs procured here and having localised sound.

Has anyone met the same problem and/or does anyone know a workaround?

Nope, never had those issues. Only with an on-board sound card I have. Sound could work or not, randomly, with media players or emulators. If that's your problem(on board sound card), just get a real cheap sound card like a Zoltrix that things will most likely work great

Sorry, in case of one DVD I found that the problem was due to the not standard DVD format. Maybe that is the problem with the other DVDs, too. I will check it out.

However, it looks like some windows DVD players are not so sensitive to DVD format as mplayer.