jrdiesel

Bare metal @ the chassis? If there is paint in the way it will affect the ground. Could be a bad set of RCA's. Run a loose set over the seats to the amp and see if it gets better. Or is it all four speakers that are whining? or just the fronts? Or just the rears? If its the fronts try switching the front RCAs to the rear and see if the problem follows. Trying swapping the amp out for a different manufacturer, to rule out the possibility that the amp isn't the issue. (as a last resort) These situations are why I dreaded car audio season every year. Viva la Remote Starter!

Sounds like a ground issue to me. Was it installed professionally and by MECP Installers? Where is the 4-channel amp grounded? Bare metal or a factory bolt? Are the RCA's ran down the opposite side of the car to your power wire? I am not familiar with your amps, so I don't know if they have a track record for producing bad whine or not, but that is always a possibility. I am using Rockford Fosgate in my truck and have no whine.