I have an '03 e46 with the Business CD. I installed an Alpine CD changer with a Blitzsafe adapter, then later an XM Direct kit (again with a Blitz adapter) and topped it off later with a gadget called iWindows, which plugged in thru the same bus and makes the windows/roof one touch up and down with the key. The last thing added was the iWindows, and that was 6 months ago.
The other day I heard a whining noise thru the speakers that changed pitch according to engine RPM. It is only heard when I use the CD changer -- no whine is heard when listening to the radio, XM or the indash CD. I suspect that either the changer or adapter has developed a problem.
Has anyone had this experience, and what is recommended? Thanks.