Gonk the only settings for Audio in the 6900 are:

Digital Output - PCM, Bitstream (Re-encode), Bitstream (Audiophile)
PCM Downsampling - On, Off
Dynamic Range Control - Auto, On ,Off
Downmixing Mode - Normal stereo, Surround Compatible
DTS Neo:6 - Off, Cinema, Music
Speaker Setting

Here's the manual - http://www.samsung.com/us/consumer/tv-vi...amp;tab=support page 35,36,37 mentions the settings and there is a chart which I don't quite understand. Maybe it's not meant to use both 5.1 and optical with this player?

I still have the Oppo 970 I used for playing cds although wasn't sure if I was going to leave it hooked up or not but I could if using the Samsung for cds is going to be a problem.