Corrected: I have a UN50M530D. Lately, the sound on the HDMI port (from DirecTv) stopped out of the blue. This despite the volume control showing should be on (no, it's not on mute). Other apps work. Seems like it occurs when I pick up and perhaps twist/squeeze the (DirecTV) remote but I'm unaware of any buttons that should do this. Turning TV off doesn't help.
Had exact same symptoms recently when too many apps were running. I'd deleted them and stopped the Hub Autorun (which apparently loaded apps automatically, reducing the internal memory available). Turns out this wasn't related at all - instead resetting the DirecTv receiver did the trick
I understand how this could possibly be frustrating. Are you using the television speaker or a soundbar/home theater system? If you're using any speakers, I would suggest changing the sound settings to PCM. If that doesn't resolve the issue (especially with it just being just one app in particular), you'll need to contact the app developer for assistance.
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