Totem Movie Player won't pass AC3 - Mint 12

[roger1]

I have a DVD with choices for both Dolby Digital or DTS and I have chosen "AC3 Passthrough" under Sound/Preferences. In the properties in Totem, the 2 different codecs (under Audio) show up (DTS if I choose that on the DVD menu and AC3 if I choose that one).

The DVD plays just fine and the sound works, but my receiver with the automatic decoder only is receiving a Stereo PCM signal from the on-board motherboard jack. I'm using a TosLink optical cable. It just isn't sending the right audio for the receiver so I'm just getting stereo and not the multiple channels.

Any ideas how to get the 5.1 working?