Channel Question/Problem

The problem I am having is channel selection for the music channels (900-945). All other channels are as they should be. I have a Series 3 hooked up to a Pioneer HD TV that also has its own internal tuner and I connect to Comcast. When I use the Pioneer tuner (not the Tivo box) all of the music channels are exactly where they should be. They line up exactly as stated in the Comcast lineup for my area. However, I need to enter a different number when using the Series 3 in order to get to the same channel. This is not just a channel-guide lineup problem. It seems that when you enter a number on the tivo remote it actually tunes to a different channel. Example: When I go to channel 925 on the Pioneer it tunes to Singers and Standards – just as it should. When I enter 925 on the Tivo box it goes to “90’s Hits”. I have to go to 936 to get to “Singers and Standards”. Does anyone know what is going on? (I’m still waiting for the folks at Tivo to get back to me.) Thanks.