If you are talking about the list of recordings, select Television in the Theater View Options, click "Add", and select "Library Item" (I think this is the correct selection). Select the new item and click "Set rules for file display" at the bottom. Select "Sort by" in the Modify Results drop-down, click "Add | A-Z | TV Channel Number". When you select the new item in Theater View then it should list the recordings by channel number. If you are talking about the Program Guide I think you have to rename the channels so that alphabetically they give you the order you want.