ARC/Simplink suddenly not working LG CX55
I posted this as a comment, but the thread was old so I figured I'd describe my setup in as much detail as I can muster in the hopes someone can help solve this issue that seems to pop up for so many users.
TV: OLED55CXPUA | Home Theater: Yamaha RX-V381 | Game Console: Xbox Series X | Windows PC
Shortly after getting my TV last November, I had issues getting ARC to work. It seemed to never be able to communicate to any of my devices. After days of trying dozens of combos, I gave up and decided to use an optical connection for sound and just live with turning everything off with its own remote. Then, inexplicably, it started working after a few months. The TV recognized the receiver's make and model without my interference and I started getting audio through the HDMI as well as volume and power communications via the remote. I assumed it had been an automatic update to the OS.
2 days ago it all seems to have disappeared, again, with no interference from me. I haven't added devices, done any update to any devices (including the TV) or changed any configuration. The Audio Out now just says HDMI ARC but no longer shows the receiver's model number as before. I can confirm that my receiver's config has not changed: ARC is active on the reserved port and the input is correct. The TV now no longer turns the receiver on/off, nor does the Xbox turn the TV on/off when it is powered one way or the other. Going through the process of setting up the Magic Remote will turn off the receiver when testing to make sure the codes work, but that's where it ends.
I have gone through a myriad of troubleshooting steps including: Resetting the AV (mute x 3). Removing all the input configurations in WEB OS and unplugging/replugging all devices in. Disable and re-enable ARC/Simplink in WEB OS. Switched from Auto to PCM format and back. Enabled/Disabled eARC. Checked for OS updates (there are none as of this post). These are all in addition to the troubleshooting steps of the external devices. Swapped cables (despite original cables having worked fine). I think the only thing I haven't done is reset the TV to factory defaults because I dread having to spend time setting up all my preferences and re-inputting all my accounts for the streaming apps.
I'm appreciative for any help or clues or suggestions of additional things to try, but PLEASE, read everything I've already done before commenting. I get extremely frustrated when people, especially support reps paid to assist in these situations, ignore all the details provided and force me to repeat myself or explain that "I've already tried that".
WEB OS ver 3.21.18
Connections: Receiver HDMI ARC-> TV HDMI 2 (ARC) | Xbox HDMI -> TV HDMI 3 | PC HDMI-> TV HDMI 4