Why no audio from Netflix?


I use a Panasonic TC-P50GT50 plasma tv and have a toslink cable running from the audio out port to my DAC which then is connected to my two channel system. I get great audio when playing Youtube but no audio when playing Netflix. Anyone know why? Is the Netflix audio stream incompatible somehow with my DAC? The DAC is a Simaudio Moon 300D.
128x128falconquest
For your information, Netflix will send audio using the "DOLBY DIGITAL PLUS" protocol if the media uses 5.1 channels.  If your device does not support this (which includes most 2-channel DACS), it will not play any audio.  Some of the movies and shows on Netflix will have 2-channel audio, which may work on a standard DAC.  That being said, Oppo 103 has an excellent Netflix interface and app!
Would this be a problem on OPPO 205? it doesn't have apps. My plan was to connect apple TV to OPPO 205 and have the sound go via analogue out to my pre amp (thinking of getting mx119 or Krell HTS7.1
I see that there is a specialist box to get an analog output from my cable box in the form of RCAs. I suppose the cable box gives a digital signal. I could convert it with an extra DAC but I would rather keep it simple. Pardon dumb question but I just had my second brain surgery!
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Perhaps the Oppo 205 is different as I see no Netflix app. But I do notice that when using an Apple TV device 7.1 will only play in 5.1

ozzy