I've seen that on many Android devices. So far you try other video players and re-encode the video to fix such a thing.
However many folk are just users so they won't know anything about my answers.
I have experienced, among others on the Samsung Galaxy Note GT-N7000, ICS 4.0.4 XXLRG a bug that causes the sound from either a video or music or skype etc. to cut out completely as if someone has muted the player when the playback is at a low volume. EG. when watching a movie with a quiet scene in it if the sound output gets low enough the sound just stops completely. the sound resumes when the volume from the media gets loud enough but it is very annoying. This problem does not occur on Gingerbread Roms only on
ICS Ways to replicate: -put galaxy note on play a movie or music with a quiet section in it, sound will cut out. I brought my phone to watch movies and tv now impossible to do either.
Nobody at Samsung wants ro help.