I have Tivo HD going through a Sony STR-DA3500ES receiver. Was having issues with the Tivo and had to unplug the receiver. Now everything's working but I can't get the Tivo Remote to control the volume and mute. I used the codes available on the Tivo settings menu but they don't work. Any idea on what code I can enter into the Tivo remote to be able to control the volume/mute on this Sony receiver? Please let me know. Thanks.