If it wasn’t set to PCM, there would be NO sound. I am using the apps built into my TV or other devices such as Xboxes, Apple TV, etc. Let me say again, I have many other devices that work perfectly with no sound drop out EVER. You are still asking the same questions, and I am giving you the same answers over a year later. This is a design flaw of the RS150b and people should know they can’t watch TV with this product and have it work correctly.
I had the same problem. The sound from my LG77G1RLA Oled TV would cut out for a few seconds. This happened at random moments but quite frequently.
I tried various HDMI cables and also the optical output, but nothing helped. I thought I would have to live with it.
Until I decided to try out the Early Access software. Not as a solution to this problem, but simply out of curiosity for new features. After some time, I realized that the issue with the TV sound had disappeared.
I’m currently running the latest official software again, and the TV sound continues to work without any problems.
I have no explanation for this ‘solution,’ but it certainly seems worth trying. The indexing after switching software versions is currently fast enough.
Good luck.