i recently started hearing this very loud and strange sound coming through the speakers whenever I would switch from DISC mode to the radio.. or when i switch from XM to the regular radio... the best i could describe of this sound is a muffled and distorted noise that completely takes over the music. I took it to the dealership but they couldn't figure out the problem nor hear it. Couldn't really argue with them because the sound happens randomly.

has anyone else faced this problem??