HomePod randomly plays music from Apple TV

Anyone solved the widespread Homepod playing random music problem?

My experience:

Gear: Homepod 2 OS 27.2, Apple TV 4K OS 26.6 (plus iPad, iPhone but not involved).

Problem: Homepod playing music at random times, at high volume, 2-3am, but also random daytimes.

My troubleshooting: Cleaned Homepod touchpad to remove dust; didn't work. Reset touch delay to 3.9 seconds; didn't work. Reset Homepod; didn't work. Powered off iPad and iPhone, music continued.

Checked music source: It is the Apple TV, playing music from my Apple Music radio station. Even if the Apple TV is power off via remote and tv screen menu the TV unit appears to start up at random times, connects to Music online, plays from my Music radio station to the Homepod. Even music I don't like or know, but Apple Music thinks I should expand my musical horizon.

My solution to date: Power off both Apple TV and Homepod at powerpoint. A hassle having to power them up daily. For what seems to be a software problem, mostly with Apple TV. But at least I and neighbours are not woken at 2am by my Homepod blasting out music at maximum volume.