But try this. Most sets only have one HDMI ARC capable port. so don't connect to that and see if you can undo that setting.
Also, check with LG if there is new firmware. I've lost count of troubles with ARC and other things due to firmware bugs.
Hi, I have a LG BH7240BW home theater audio system and I recently learned about ARC. I used Optical before, the Optical output on my TV broke so yeah.
Anyway, I've fiddled with it for a while without results and today I saw that I missed one checkbox in my TV settings. Checked it and my HTS lit up saying ARC was activated and displayed ARC in the little display. I then pressed Home to go to the HTS Settings to test the speakers and then I never managed to get ARC to activate again. I've tried turning it on and off, do a factory reset, but nothing I can think of works.
The TV still notifies me it's using an external reciever and deactivates the TV speakers, but it's like the HTS doesn't even know about it.

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