Read http://forums.cnet.com/7723-13973_102-633209/samsung-un55h6350-optical-out-doesn-t-work-with-apps/?tag=posts;msg5643858
HDMI ARC is too hit and miss. I've read folk spending weeks on it. I won't.
Bob
I have the subject Samsung 4ktv. It is connected to an Onkyo sr-705 receiver via a Hdmi cable.All the sound is driven to the external speakers.
Everything works perfectly except the smart apps like YouTube, Amazon etc. the sound only comes from the TV. I cannot get it to play through the external speakers. I have researched this but cannot find a solution. Please help.

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