Stock 12 disc changer question

Is the stock cd changed just crappy quality, or what? Sometimes, when it's playing my cd's, it plays them horrible quality. They sound all scratchy and staticy. The manual says that sometimes in high humidity or certain temperatures it will do this. WTF is up with that? Is this normal? The head unit still plays the CD's fine, but the changer will play em like crap at particular times. Is there any way to fix this, or will I just hafta stick w/ playing them all from the HU during these times?

I sure hope mine doesn't start doing that. So far I haven't noticed any thing. I would see if there is some type of cleaning disk that might help or something.