yeah i notice a whine like this guy is talking about in my pioneer deh-p4300. I thought that maybe it was my amp, but now that someone intelligent has said that pioneers have a problem with this, it seems logical.
Well guys I tried regrounding the rcas at the hu for both my fronts and subs...problem solved...no more whine and it sounds much better. thansk a bunch guys. if anyone else has this problem try it, it was the only thing that fixed it for me.