There is always this...
http://www.amazon.com/ViewHD-Premium-Audio-Extractor-Converter/dp/B00AHS8LD8/ref=sr_1_1?s=electronics&ie=UTF8&qid=1392521065&sr=1-1&keywords=hdmi+toslink+converter
Supposedly it will allow 5.1 to come off, even when connected to a TV. It strips the audio first. These things are hit 'n miss. Some really do it, some only do it if the next piece is not a TV.
http://www.amazon.com/ViewHD-Premium-Audio-Extractor-Converter/dp/B00AHS8LD8/ref=sr_1_1?s=electronics&ie=UTF8&qid=1392521065&sr=1-1&keywords=hdmi+toslink+converter
Supposedly it will allow 5.1 to come off, even when connected to a TV. It strips the audio first. These things are hit 'n miss. Some really do it, some only do it if the next piece is not a TV.