I would definitely be interested, since an outboard DAC could easily eliminate that horrendous 50dB stereo separation and 18kHz rolloff in freq resp! Either Toslink or coax would be appropriate, since most DAC's will take either, although lower-end units only have Toslink. I think $50 would be reasonable, depending on the complexity of the circuit, although I have a bad feeling it would cost more...at some point ,the sound improvement from a digital output board + DAC isn't justified by the cost (e.g. the money could be put towards better spedakers), but oh well. :-)