You can add me to the list of interested people for this module in any of these forms (my car stereo wants coax, and my home stereo/PC will take either). I prefer an internal solution though.... simply because then you only need one board per player, as opposed to one board per installation location with the dongle.

I didn't see any mention in this thread regarding how the interface between the player/sled will be handled. Since we are considering having an optical output on the player, I presume the assumption is that extra connectors will be added to the rear of the unit.

In the case of an internal unit, I was planning to reallocate the pins for the the mic input (or rear outputs, etc) on the docking bay connector for the coax digital output. The docking sled wire harness would be modified such that the this mic connector would be replaced with an RCA (or maybe use a mini-jack to RCA adapter cable). Anyone see any issues with this plan?

As far as the final solution, here's my suggestion:

Offer the internal kit with coax output only. Everyone gets to keep two drives. Coaxial output is the default output. This has the advantage of being able to be transmitted over the docking bay connector so that adding an extra rear jack isn't required (but optional if you don't want to sacrifice something on the docking connector). Plus I imagine the cost would be lower for the base kit since you don't have multiple ouputs, with the associated electronics and connectors, etc.

Then, have an external dongle module available that could convert the coaxial signal to optical.... in fact, these can already be purchased as retail products for home use.... the links below are for such adapters, one is $25 and the other $30. The only problem is that they are intended to run off a 6 V DC.... so something would have to be worked out to make them run off 12 V DC (or maybe they could run off the 5V from the player).... I have seen schematics for these and they seem pretty simple.... one could probably be made for even less if you wanted to make one as an option. Or perhaps a more thorough search would turn up a unit in the same price range that already runs on 12V....

http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=580&item=SP-COAX-OPTICAL&type=store

http://www.cablesandconnectors.com/01700-01.HTM

I prefer not to have add an extra connector to the rear of the EMPEG. For one, their would be the same problem already encountered with the ethernet connector... you can either accept it as not being dockable and manually plug/unplug the cable when you install/remove the player or deal with the problems of trying to make a toslink, RCA, or mini-DIN connector dockable in the same manner others have done for the ethernet connector (although this would probably not work as well for these audio types of connectors). Either way, with the optical interface, this means that the optical cable and output jack are exposed whenever the player isn't docked.... and you have to worry about dirt, dust, etc over the long term (you could always put one of those Toslink blank covers in place when the player is out, just don't forget to remove it before throwing the player in the sled!). Lastly, I am not too excited about making any permanent mechanical modifcations to the rear chassis (drilling holes in it, etc).

I dunno, just my two cents.

As I said, I'd be interested in this in any of the variations you presented.