I reported the first four episodes of Dollhouse last night. They are SD, but are still advertised as having 5.1 Dolby Digital nonetheless. I have my iMac connected to my receiver with an optical digital cable.
The option to changeover to 5.1 appears in iTunes when playing back the episodes, but when I do that, the sound completely cuts out. My best friend is having the same problem. I've reported the issue to Apple, but they seem to think that issuing a credit is a sufficient fix for this. I'd rather have what I paid for.
It's doubly aggravating because now I find they seem to be ignoring this problem. I'm not sure why it's so hard to fix. I know you can get 5.1 without any problem off torrent sites, but I don't want to go that route. But it is
really pathetic when you can get higher quality illegally than legally, don't you think?