Stereo & Electronics - Sub volume fading in and out...

Just got done putting a 10" Alpine Type E sub in my 99 Z28 this weekend. Running it off of a Kicker amp which gets its signal from the MTX re-Q5 LOC. I set up the sub/amp volume to my likings and for the first day or so it was fine. Then last night the sub was hitting like I wanted it to, then all of a sudden the sub started hitting really freakin hard. Which isn't really a bad thing I guess, but its not consistant and has me baffled. I like my boom, I just want it to stay at where I set it up. Anyone have any ideas as to why it would fade in and out? Do I need to get a higher rated alternator? Bad connection?

Better put this info in here: Stock head unit and all other speakers still running through the Monsoon amp. The Re-Q5 is pulling the signal before the Monsoon amp. Its pulling the signal from the sail panel speakers.

Speed-controlled volume?

i don't think it'll help but, i had a volume problem in one of my older setups and it ended up being a loose ground wire...
it getting more power than normal.....maybe a short somewhere? though i would think it wouldnt work at all with a short, or it'd blow a fuse or something....

I have the SCV shut off because I find it really annoying. I'll have to start going through the connections and looking for something loose or not making good contact...Yay! ha ha.