I originally posted this under two sound cards but recived no response. sorry for the double posting. If I could remove it off of the other thread I would. Anyway ....
I just ordered a Zotac ION ITX MOBO and a mini form box that I am going to use as a fan-less Myth TV frontend. The video stream and the related audio processing is handled by the inboard nVidia chip and sent out the HDMI port (combined video and 7.1 audio) to my multi service- multi zone amplifier. The multi service amp can process two input signals and put them out to any combination of zones I require. This configuration allows me to watch movies/TV in the family room while my wife listens to a music stream in the kitchen. I want to avoid the cost and more importantly dealing with the increased thermal load of second streaming device in the enclosed family room audio cabinet just to stream music. I could buy a network enabled amp, but the cheap ones go for $1700 and up. Besides, I already have a nice amp 2 year old amp that I can't see tossing.
given this I have two questions:
1) Eliminately I would I would like to have the MOBO run both streams, but is it possible to direct the 7.1audio/video stream out of the HDMI port and the music stream out of the optical digital audio port?
2) if a need a second sound card, I am going to have to go with an external USB card, because there is no room in the MOBO box and I want to avoid the extra thermal load.
I'm not sure about the first question, but I do know using a USB sound card will place load on your CPU, which may impact the performance of your media streams as you try to direct 'em to different parts of your house.
1) I doubt you can do that with the mobo you have. You could do this on a mobo that has a better codec (such as ALC889).
2) Not 100% sure about this but here goes. if you get a external USB sound card, wouldn't you need to use something like ASIO4ALL to get two separate streams? Are you sure ASIO4ALL (or some other software) can handle the setup with two sound devices?
EDIT: you just say mythtv. if you're gonna be running it on linux then it's not about ASIO4ALL of course. but my hunch is you would possibly have to deal with something like JACK instead.