I read through the FAQ entry about outputting surround sound from my Mac but it was written back in 2007. I'm curious what the current state of surround sound is on the Mac platform.

I have a 1.83Ghz C2D Mac mini and a late 2008 unibody Macbook and I'd like to use one or the other for outputting to my InFocus 4805 projector and older receiver. I have the proper DVI/M1 connector for the projector and it seems like the video side is fine. The audio side has been frustrating.

My receiver doesn't have any optical inputs, I'm limited to Dolby Pro Logic II and it seems that nothing I try will result in proper surround sound. I have no trouble with audio from my Linux system under the same conditions, just with my Macs. I've used both the internal audio of my Mac mini and Macbook as well as an M-Audio Fast Track USB.

Is there anything I can do or am I simply a lost cause because I don't have optical in on my receiver?

My receiver doesn't have any optical inputs

Does it have coax in? Gefen makes an optical to digital coax converter which would work plug and play with your Intel Macs.

I've used both the internal audio of my Mac mini and Macbook as well as an M-Audio Fast Track USB.

I don't think the Fast Track USB is one of the M-Audio interfaces than can do AC-3, so you'd need a different model. I have a Firewire Solo, got it when I bought my first mini, the G4, and it does pass through AC-3 to an AVR, but...that's not the answer anyway. These devices haven't worked well with Intel Macs and would be throwing good money after bad. In general, M-Audio driver support is terrible, even if you do spend more on a better M-Audio firewire or USB you'll pay later when they fail to re-write drivers in a timely fashion.

Is there anything I can do or am I simply a lost cause because I don't have optical in on my receiver?

You could try a different M-Audio device, the cheapest one which (supposedly) does AC-3 passthrough is the Transit (but again, I don't recommend it) or you can get that optical to coax converter or do what we all do--get a better AVR that has a bunch of optical and coax audio inputs.

It's not that perfect AC-3/DTS passthrough is guaranteed with all file types if you do go optical, but at least it has a chance of working much of the time. Your success will depend on what OS version and which software or front end you're using.

the cheapest one which (supposedly) does AC-3 passthrough is the Transit (but again, I don't recommend it)

My Transit works just fine despite the lack of drivers for SL.

Andrew, right, but the real question I was trying to answer for the OP is: given your experience, would you recommend that he buy the $79 Transit now to solve his problem versus putting his money toward 1) a better AVR with optical in or 2) a much less expensive optical to coax converter? Which do you think makes more sense?

With the Transit in SL, which Intel Mac model are you using it with, and with how many of the following are you able to get reliable AC-3 passthrough:

1. Apple dvdplayer.app
2. VLC
3. Front Row
4. EyeTV
5. Plex

Thanks for the input. I've been talking about a new AVR for months but haven't decided on one yet.