Sort of a strange problem here. I have an Apex AD-600A, and when I popped in my UHF disc, the player became VERY loud all of a sudden when accessing the menus (the motor on the drive was shaking the unit). I tried a different disc though (Hitchhiker's Guide to the Galaxy) and it was back to being quiet (no time in between to "cool off" or anything). Any idea why this could be? I could see if it was all discs, but just a few? I've noticed it on other discs as well, but it's particularly bad on UHF.