Open up the speakers and check for any damage i.e. burnt out components.
Here’s the ifixit Sonos One Repair guides that will help to do this.
I cannot find the schematics or a service manual for the speaker so finding out what the problem is, especially if it is not obvious and then replacing any faulty part(s) if their value markings have been obliterated will be difficult.
If you can’t see any obvious damage or even if you can, post some close up images of the board where the power connects to. Here’s how to do this on ifixit Adding images to an existing question