Unfortunately, the commands in the config.txt did not have any effect either.
Thanks for testing. HDMI modes on both logs are the same, so that part of the pass-through works. Two more tests:
- Use different amounts of output channels on LE's audio settings. Because it's a surround soundbar, it maybe doesn't accept the default setting of two channels (other channels are encoded at those two).
- Detach and attach the HDMI cable while RPi is running.