MythTV Sound Setup

[Carrot06]

I currently have AC3 passthrough turned on for watching DVDs and Digital TV. The problem with this is that when I select certain TV stations, if AC3 is available, this is selected by default rather than MP2. How can I change the default audio to be MP2 when available rather than AC3?

[nickrout]

one kinda wonders why you would do that, are you saying these stations transmit two audio streams?

[Carrot06]

yes thats correct, one with AC3 3channel surround sound, the other MP2 2channel. The worst thing is its only 1 of the 4 free-to-air channels that does this, the others only broadcast in MP2.
The reason I want to do this is because when just watching normal TV my stereo is not turned on. I generally turn my stereo on only when I'm watching a movie.