Well, I haven't gotten them to work with MJ yet...but steps are being taken. Keep in mind my knowledge is based on working in Win2k, so there may be differences with the "consumer" OSes.
Bit-perfect playback is needed when dealing with DTS CDs. The decoders are very sensitive to mangling of the bitstream. MJ 8 has an alpha ASIO plugin that is a start. MJ 9 integrates the ASIO driver into the main application.
ASIO is a different driver model that lets MJ send the bitstream directly to the soundcard without going through the native Windows drivers. Unfortunately, the majority of soundcards that have ASIO drivers available are the "pro" soundcards. Check out RME, M-Audio, etc.
DTS doesn't work yet with MJ in my case because the MJ ASIO driver sends the bitstream to the first channel on my M-Audio sound card which is unfortunately an analog channel. I can use my sound card interface to map the analog channels back to the digital outputs, but the card performs some upsampling and mangles the bitstream into static. I have to wait until there is some kind of interface with MJ to actually select the output channel on the sound card. (Any news on that, guys?)
FWIW, I have successfully played DTS CDs using WinAmp. You need the CDReader plugin and the ASIO output plugin. After that, you should be okay (as long as your sound card supports ASIO).
ASIO sounds better to me than the regular SPDIF output on my card anyway, so i love the steps that MJ 9 is taking!
Best,
Brad