Have you considered converting them from DTS-encoded WAV to a regular .DTS file or even straight-up multichannel FLAC? It'd be more compatible with most players. I converted mine eons ago...IIRC I used a tool called "wav2dts" to convert the encoded WAV to a straight-up .DTS format (which MC will play); from there it's your choice to convert it further to FLAC.
Cheers,
-Doug