Running the sp-dif signal out of a mini-jack is ok with me. It seems like that mic input is never going to be used, so sacrificing as a sp-dif out works for me. I don't need optical out as my DTS decoder uses sp-dif rather than tos-link.

As for DTS, there are two kinds. The kind on DVDs is 48KHz, but the kind on DTS CDs is regular 44.1KHz (it has to be as it must play back on regular CD players). I plan on using the later.