As it seems several others have posted (see links below), my Sonos One died this week. It’s approximately 2.5 years old and one of two I own, in addition to a Port. I received the same “resolution” from Sonos Support - here’s a 30% discount on a new (?) one, sorry about your bad speaker…
The speaker sat on the shelf plugged into a power surge protector outlet for the duration of its life. The only thing I did (the day before I noticed the failure) was flip the breaker to that outlet to work on an unrelated wall switch. Therefore, something akin to unplugging and plugging the speaker back in fried it.
There's clearly a fundamental issue with a component in these speakers and Sonos isn’t doing much of anything to help.
Others:
https://en.community.sonos.com/components-228996/sonos-one-no-longer-powers-on-6838698
https://en.community.sonos.com/troubleshooting-228999/sonos-one-non-responsive-6831878
https://en.community.sonos.com/troubleshooting-228999/sonos-one-dead-cannot-power-up-6849037
