I bought my brother this receiver for Xmas, and now he's having trouble setting it up. He lives in a different city and I can't find the owner's manual online to try and help him. We've fixed several problems so far, but this one remains. He claims he can't adjust the rear levels independently. Surely this is a mistake. I told him to try playing a 5.1 disc and then running the test tone. Any Sony owners out there who can help? Thanks.