Quote Originally Posted by WhiteGT View Post
Is this an issue with the pioneers? I have never had this problem with any other deck I have had.
Yes this is mostly involving Pioneer HU's. It seems that when you use the RCA's on a lot of Pioneer systems, they are not as well grounded as most other car stereo's RCA hookups are. Others can produce the whine, but it seems mostly confinded to Pioneer HUs.