Interesting development!

When I got in the car yesterday the whine was terrible...however...now listen to this..when i push the very top of the Rio in...with a bit of pressure...the whine pretty much goes away...so it seems like there is a bad connection somewhere within the head unit that when i put pressure on it it becomes better.....

i took out the HU and opened it up and checked the wiring on the rear connector and everything seems to be very tight took off the connector and checked the connector..very solid

perhaps its on the sled?