There's also some chatter that Apps have to support this audio pass through but when I see ARC, I have the optical cable ready.
I have a Samsung UN55ES6150k Smart TV and a Pioneer VSX-1021-k AVR. Both are supposed to support ARC. The single input to the TV is an HDMI cable from the AVR HDMI Out to the TV HDMI2(ARC) input. Works fine from Blu-Ray & DVR. However, When I stream from The Amazon app on the TV the sound only works through the TV speakers. If i set the TV to External speakers there's no sound at all.
I've read a few threads on similar problems but none of them has solved my problem.