HDMI audio is fine on my msi media live.
I believe you will still need an amp to drive speakers from the media live.
You are right, what i was trying to do was hook up my Media Live in the Den to some Computer Speakers i had from my gaming machine a while ago, they support 5.1, and i have some RCA->Mini-Jack adaptors to connect them.
The main reason i'm keen to get try it out is i have some AC3 audio in some of my MKV files, and these dont seem to play audio when using the analog A/V out, I though theres probably an on-board Dobly Decorder that can decode the signal and out put on the 7.1 audio panel on the back of the MSI Live..
Its not a train smash, but would be nice when using the MSI Live in other rooms where you don't necessarily want an AV Receiver but would like some decent Surround audio, like the bedroom. I've already ordered a Yamaha AVR for my living room... can't wait to hook that up, hope serial control wont give me hell - still struggling with IR control from my Samsung TV