I feel like your problem is the HDMI CEC. I have a Samsung TV also and they just updated the software to activate the eARC and ever since, I had problems with the audio. Turn off the CEC on the TV and I bet it will fix your problems. I did a factory reset on my tv and it made a big difference but the problem is not the TV, it's the CEC in the zidoo box. Even if the CEC is turned off in the zidoo box, it still messes with the receiver and TV's CEC connection. I've mentioned the CEC problem a few times here and they don't seem to care. Even tried a lindy CEC blocker on the zidoo and it didn't block it. so I just leave it turned off on the tv and the receiver and the box and everything seems to be fine with the sound.