I can trigger it occasionally on tvOS (especially directly after wake from sleep when I would assume any normal computer is booting up background daemons) just moving the cursor around on the Home Screen. Seems to be tied to eARC being active at all. Worse more often in 2022 hardware variant. Not resolved through 8K HDMI cables, especially since the sound is being generated by Home.app on the Apple TV and sent to the HomePod one foot left of it without an HDMI cable.

So, yeah, I’ve decided that modern 4K+60-120+eARC+Spatial sound slightly exceeds the Apple Silicon capacity of the bargain-priced models.