AhHH. A cable card. I wondered but wasn't sure.
I'm not familiar at all with cable cards to know if it will take audio from the HDMI input and relay it out to the Toslink output. I'm doubtful but totally uneducated there. I'm sure someone here can respond to that definitively. Perhaps if you knew the make/model of the tuner card, it would be possible to research it's feature set and see if it's likely to do so.
Even then, I think it will be a non issue. Even if your cable card does process it and loop it through. Your receiver will very likely only accept digital input from one single input, for a given task, at a time. Therefore if you set up your receiver so that in DVD mode it only accepts input from the DVD Tos and that in TV mode it only accepts signal from the TV Tos, then it shouldn't matter if your cable card is trying to loop it through. If your AVR auto-senses and can't be nailed down, I suppose it's still an issue. Also, when you say "processor" do you mean a dedicated audio processor or an AV receiver. I have been speaking from a receiver point of view but either way, if you can program the inputs, your laughing. Again, a make and model would help.
Of course, the easiest thing to do is simply hook it up and experiment. Play a DVD and leave out the optical connection that goes from the player to the receiver. Set the Receiver to take input from your TV Optic in and see if you hear anything. Question answered.
Sorry this is long. Someone who knows for sure may be able to wrap this up in sentence or two.
