sudden line noise from pioneer deh p690ub

Setup:

1986 Honda Accord DX

Pioneer Premier DEH-P690UB

Planet Audio 6.5" in all 4 locations

In the trunk:

Memphis Audio 16-MCA3004 and 16-MCD1000

Memphis Audio 12" single coil sub in sealed box (I know, I need something else, but it's what I got right now)

Kinetics power cell

Alright, so everything was installed something like... near 2 years ago, except for the head unit, which I had installed early this year.  Everything has been sounding fine in the past, but today I'm getting HUGE line noise that fluctuates with my engine RPMs (this is alternator whine, right?).

I took a search around, and it sounds like this is something that happens with Pioneer head units - so can I instantly write this off as being a problem of the head unit?  The install and HU is under warranty for another 4 years, so it's no money or time for me.

Found out what it was!

The 4 channel's rear speaker RCA connector has a outer collar that is loose.  The shop that installed it used Memphis RCA wires, which are adjustable in teh sense that they can be crimped a bit to grip a terminal better.  However, the "pro" crammed the RCA wires on to the terminals instead of adjusting them, among other wonderful things I've found in the past.  Earlier in the year, I had to remove the RCAs because I had to troubleshoot my old deck (it lost all high signals on all but the front right - it was ollllllddd), and one of the terminal's sleeves got pulled off.  I was able to push it back on (it connects with prong-shaped things), no harm done, but I made sure to adjust those RCA cables.

So, I'm guessing that things are out of warranty now and I might just have to live with things - I might see if I can get the prongs bent a bit outwards for better grip.

Thanks all!