Something or other by Samsung, a couple of years old (whenever the big-box stores were giving away The Dark Knight with it). It isn't a big deal...95% of what we use the system for is movies or TV. Just using it for music during cleanup from the renos.

I'll check it against some pristine CDs and see if it's still doing it. If it is, time to drag the iPod out of hiding (from the kids, who discovered how to look up naughty videos on YouTube).