Cable box to outboard DAC

Some (not very many) support PCM out of the digital output. A lot of them also can be software configured for specific cable companies. So, its kind of hard to tell whether your RCA digital output can be fed into a two-channel DAC or not. Most cannot.

That said, I've got a Scientifc Atlanta 8350HD, and there is a menu setting where I can tell the box what to send over the coax digital out. That works fine. You might just check the menu settings to see if there is some ability to modify what goes out of the box. AC3 through a 2CH DAC will not sound like music.

On one box I have, "other" = PCM. On the other box, its some strange format and I have no idea what it is. No way to tell for sure w/o hooking it up to a DAC, unless you find a really, really good tech in your CATV company's tech support...

You might also try digging around here:

http://www.scientificatlanta.com/consumers_new/CableBoxes/2200.htm

They have manuals for most of their boxes. I note that Sci Atlanta describes your box as supporting "AC-3" and "Musicam" digital audio support.

An AC-3 -> PCM "converter" is a digital HT preamp, like a Theta Casanova or Casablanca. So, yes, converters exist, but it won't be cheap. Nothing, to my knowledge, will do AC-3 or Dolby to 2CH with little or no configuration, staying in the digital domain, and for cheap.

Until cableCARD compatibility is truly here--and it isn't--there is no guarantee that a 3rd party cable box will work with your cable provider's system. Before plunking down money on a cable box, I would ask your cable company techs for compatibility information first. Esp. w/digital cable.