Hi,
Open up the speakers and check for any damage i.e. burnt out components.
Here’s the ifixit Sonos One 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
crwdns2934105:0crwdne2934105:0
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crwdns2944067:02crwdne2944067:0
My Sonos One SL's power supply died 2 months out of warranty. No support from Sonos, so I'm trying as well. Slightly different set-up. The seal on the base has two-parts: rubber and a plastic adhesive strip that covers the screws. Also, the 4 T8 screws in step 7 are covered with adhesive covering that needs to be pulled away from the chassis. I haven't removed the T8 screws yet as I don't have a T8 bit.
crwdns2934271:0crwdnd2934271:0 ellibtwo2@aol.com crwdne2934271:0
Hi, I have the same problem after a power surge. Where do I get sparepart ie new power adaptor board?
crwdns2934271:0crwdnd2934271:0 Bjorn crwdne2934271:0