I'm having a problem with skipping audio on two different machines, both with up-to-date Ubuntu 12.04 Desktop installed (one 32 bit, the other 64)

It doesn't happen all the time (maybe once per song when it gets bad), and happens regardless of the program creating the audio (could be streaming through Grooveshark, or playing files with VLC, etc.)

Does anyone have any ideas as to why this is happening, or how I could fix it? I don't really even know where to start.

Thanks!