Problems with car stereo

Jul 5, 2009
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Not sure where the best place is to post this question, but I have a 1 y.o. Hyundai with a factory system. It sounds decent enough, but every so often, I will listen to a burned cd which sounds like total shit. It sounds like a skipping cd, in that it goes quiet and then loud again at the same interval. But, the cd is proceeding at a normal speed, and I will have other songs on that same cd (but from a different album) that won't have that problem. The songs from that same album will all be pretty much unlistenable because of this though.
Since it only happens with some albums, I can imagine that if I took it in, they would say it is working fine. Any idea what the problem is here?