My new Samsung purchases: UN55TU8000FXZA Crystal TV (2020) and HW-T550 (2020) soundbar. I also bought a high speed HDMI cable.
I connected soundbar ARC out to the TV's HDMI ARC port. When I turn it on, the soundbar displays DIN, then TV ARC. A pop up window on the TV says "Please connect your device to the HDMI ARC port." It is connected there, and the sound source on the TV shows [AVI] Soundbar T5 Series (HDMI), with the sound mode at DTS Virtual:X. So it would seem that it's working. Occasionally the TV will revert to TV speakers, but I can change it back through the sound menu on the home screen. It's like the TV isn't recognizing its own HDMI ARC port. And the remote turns both devices on, and can control both devices, but it only turns the TV off.
I unplug the TV overnight as I've seen unplugging TV will help.
Help! My efforts today have made it worse. Now it won't even see the soundbar HDMI arc option. Or it appears for a second and then disappears again.
Any advice for me? Thanks!
The original poster was me. I was getting all verklempt over losing what little HDMI arc connection I had managed to get. So after several hours of fussing, changing out cables, trying different settings, unplugging, replugging, etc. I thought I was going to be stuck listening to my audio on optical. I reconnected a blue ray player and a Roku to non-arc HDMI ports. Finally, I thought I'd try one more HDMI cable on the soundbar. Not an expensive cable, all it had on the plugs was the brand name - Insignia.
It worked! Now I've got my HDMI arc soundbar set up again. I still get a pop up (only once per viewing session) that I need to plug my device into an HDMI arc port (when it already is). But at this point I'm willing to put up with that.
What me off is that this is such a widespread problem, and Samsung doesn't say or do much to address it.