Sonos One dead (cannot power up).

Is it properly plugged in? Have you tried a different wall socket? What did Sonos support suggest when you contacted them?

New or used? If new, return it to the place of purchase for an exchange under warranty - if used, then perhaps contact the seller, that’s all depending on the terms of the sale. 
HTH

There is definitely a design issue with the one SL.  I have been lucky that all of my units have been replaced under warranty but I have returned 8 of the one SL speakers and I only have 7 of them.  Some have died at the year mark, one lasted just a couple days … all of this over a multiple year period.  I have an arc, two subs, a port, and amp with no issues. Also no issues with any electronics in my house. I am guessing Sonos designed these to such a low price point. They cut some corners and robustness in their design.

Odd, I have six or seven of them, most from within several months after they were introduced in 2017 (the One SL in 2019) and not one has failed. Wonder what the difference is between our two environments. 

Probably doesn’t help they replace the broken units with refurbs. Have lost track of which ones I have actually sent back at this point. Possible it is refurbing the refurbs.  Could be environment differences, but back to my design comment.  They clearly are not very robustly designed, should be able to handle different environments.

FWIW - I have two One SL’s (purchased as a set in early 2020) and they’ve both been absolutely fine - I initially used them as Home Theatre surrounds with a Sonos Beam. I later had them stereo paired in the Kitchen and now have them standalone in two bedrooms - they’ve been used regularly over the years (almost daily use) and both are still going strong. I’ve been more than happy with the two speakers. The One SL’s seem very well built to me, as good as every other Sonos speaker that I own.

Mine Sls have survived but I do have all connected to quality surge suppressors.

Just to add: The One SL’s I have here show in the Sonos App as hardware version 1.28.1.6-2.2 (if that info. is useful at all)?

To me this high failure rate indicates something in your environment is contributing to the failures. The obvious candidate causes would be power line transients or static electricity discharges.

Power line transient intensity can vary from circuit to circuit. A rogue appliance on a circuit could cause major trouble on its circuit and less trouble on another. A wiring fault can contribute to the issue. Each unit has an ability to withstand a certain level of transient. In this respect it’s possible that the ONE SL’s are the weakest unit using the outlet. This does not imply a defective design, only that the specific level of transient is too low to damage the other units outright, however, they could be suffering long term damage. If you are using transient protection, it could be improperly installed or failed. After a certain number of large transients the protector will fail and it is not practical to test these units in the field.

If any of your units are wired to the network, the network wire is a potential source of transients from nearby lightning strikes.

Static electricity discharges are typically more of an issue in winter months because the relative humidity is lower. Do you touch the controls? If so, have you noticed any shocks?

Yes, it’s possible that there was a bad batch of units, but it is unlikely that all of your units have come from that batch. Based on reports from other users on other models, SONOS is aware of a few problem batches and has been generous with replacements for these units. These units are identified by serial numbers.

I have literally hundreds of “sensitive” electronics in my house. None of them fail. Only marginally designed one SLs.