Set up the player to cap the volume at 0 if you're worried about getting into the distortion zone. That "overdrive" area is pretty much the same thing as turning your head unit beyond 3/4 range (which is generally close to where you get the loudest undistorted output).

Also, if you're linking a few devices that have volume/sensitivity/gain controls, just make sure your cumulative settings don't cause any distortion or clipping. I had some pretty crappy output on my first day because my Clarion HU (which I'm using as a preamp) was accidentally set to high sensetivity for its AUX inputs (where I have the empeg connected). I was overdriving my main speakers with the empeg volume locked to 0 and a number of songs sounded like crap.

I've got things set up now to get loud enough to cause severe ear pain yet with no distortion or clipping. I still have some sensitivity adjustments to make for my rear speakers and subwoofer to balance everything out a bit better.

Bruno