TV setup, Blu-rays causing problems?

Hi everyone, I'm new here and I have a rather specific question. I've already used the search function but haven't found anything suitable since my setup often includes other devices, so I'm trying my luck here.

I recently bought a brand new TV (LG OLED G4) and a new soundbar (Bose Smart Ultra). Everything works perfectly when watching TV—or rather, Netflix, Prime, Disney+, etc.—and gaming, but Blu-rays are causing problems. If relevant, the consoles (Nintendo Switch OLED and PS4 Pro) are connected to a Philips Hue Sync Box 8K, which I use for Ambilight.

I always play Blu-rays on my PS4 Pro, up to the main menu of the film everything works without problems, but as soon as the disc starts the soundbar stops, it is switched on, but

There's simply no sound, so I have to manually switch to the normal TV sound, which I'd rather avoid. Additionally, the TV turns off after about 10 minutes, which can be quite annoying when watching movies. I've tried all the sound and power options, but I haven't found a solution to either problem. Incidentally, the dropouts and soundbar issues don't occur when playing on the PS4.

Here again is the exact connection sequence, I'm also attaching a sketch.

Soundbar -> via HDMI 2.1 -> TV (eARC HDMI)

HueSyncBox8K -> Via HDMI 2.1 -> TV (HDMI1)

PS4 Pro and Switch OLED are connected to HDMI Output 1 + 3 with Original HDMI.

I am grateful for any help!

Greetings Jasmine