In the latest stable version of xmms (1.2.10) as well as in previous versions, I’ve noticed that songs would skip a note or two while I was doing other things. It became annoying enough that I eventually stopped listening to MP3s while working on my computer. I finally decided to search for a solution and learned that there are two common causes of skipping when playing MP3s with xmms.
The first is when DMA is not turned on for your hard drive. To check, run ‘hdparm -d /dev/hda’ (assuming you’re playing MP3s on the hard drive located on the first drive on the primary IDE controller). The output will say ‘using_dma = 1 (on)’ if you have it turned on. I already knew my drive had DMA enabled, but I hadn’t thought about that affecting xmms.
The second cause of skipping is when the buffer size for the output plugin is not large enough. To increase it, go to the xmms Preferences (Ctrl-P) and hit the ‘Configure’ button. I changed my buffer size to 10000ms (10 seconds) instead of the default of 3000ms (3 seconds) and that seems to have done the trick. Now I can listen to MP3s again without having to endure skipping.