alternator whine in 03 suburban

Hi Guys,

I am working on an 03 Suburban with Bose.  I installed a Kenwood 342U using the GMLAN2SR.  I thought the radio was working fine, but it starts to whine when you drive it.  When you start the vehicle and rev the engine, everything is fine.  There aren't any problems until you drive it.  At that time it starts to whine.  The pitch changes with the RPM's.  I ran a new ground wire.  I would prefer not to run a new power wire, but I will if I have to.  Is there any way to test this to see what is causing the problem?  I could run power and ground from outside the vehicle, but it doesn't whine unless it is moving, so that wouldn't really help much.  Any thoughts?  Has anyone else had problems like this?

Thanks in advance!

Brian

While driving the vehicle, place the shifter to neutral and rev the engine.  Is the noise related to the speed of the vehicle or the engine RPM?  Is ther a VSS wire on that harness?  If so, try moving the harness as far away from the radio as possible.