MKV Files do not play with SOUND

Hey, I have most of the forums and understand that most MKV files will not play with sound because the WD TV HD does not support DTS. My Full HD TV has an OPTICAL DIGITAL AUDIO OUT port. Is this a port which a Tosilink can connect to? If it is so, will I be able to get sound on my MKV files by connecting one end of the tosilink cable to the WD player and the other end to my TV?