How can I make my 609 select cbl/sat when I turn it on?

My TX-NR609 is connected to a Samsung TV that supports Samsung's flavor of HDMI-CEC (seems to be close enough to Onkyo's dialect). I'm also using an AT&T U-Verse STB (no CEC). When my U-Verse remote sends the power on signal to both the STB and the TV, the receiver dutifully turns on (the TV told it to). After a few seconds, the receiver switches the input to TV. This is, no doubt, correct behavior, but that's not how I've got things hooked up. Since the STB is connected directly to the receiver, I need to manually select the CBL/SAT input every time I want to watch TV. Is there any way I can configure this to default to the CBL/SAT input when the TV turns on?

For the time being, I connected the STB to the TV instead of the receiver and things are working nicely, but now I need to switch the TV's input to the receiver when using the receiver's apps - not terribly intuitive. It's confusing to the less tech savvy members of my family (everybody but me, it seems).

Curiously, I see the video from the STB on the TV, but no sound. Maybe I'm simply missing one piece of this puzzle?

Suggestions?