Since ARC is hit and miss and will confound all as it stops working, try the usual Optical connection from either TV or player to the HT.
Bob
I have the LG HT904TA All in one Home Theatre System plugged in to my LG 50PS60 Plasma TV with a HDMI Cable. All has been working fine for just over 4 yrs now.
Recently, while watching a DVD with surround sound on, suddenly the sound from the speakers stopped. So I rebooted both the TV & Home Theatre & tried playing the DVD again. The sound came on briefly for 1-2 seconds & went silent again.
I tried playing a program on TV & the same result, sound comes on 1-2 seconds & then silence.
So I switched to the sound from TV in built Speakers & sound is fine. I can play TV programs & DVD with sound from the TV speakers without problem.
However, if I switch the sound to the Home Theatre I get sound only for 1-2 secs & then silence (this only if I reboot the Home Theatre first).. if not then silence throughout. The DVD player in the Home Theatre works fine.
I tried with a different HDMI cable, same result.
Any ideas from anyone?

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