Sonoff S40 lite (Zigbee) reliability

Has anyone had reliability issues with the S40 smart plug? I recently purchased some and they no longer respond within two weeks of being paired. Unplugging them and plugging them temporarily “fixes” the problem. I’ve unpaired/repaired them with the same results.

More interesting when they stop responding to commands the override switch on the plug also no longer works. Which suggest a hardware issue with the plugs

I use zigbee2mqtt with the Sonoff usb coordinator. I have three plugs in service and they are near repeaters. One is within 3 feet of a Sonoff mini relay (relay works flawlessly). The others are within 10 feet of Zigbee light bulbs. All show links with decent liquidity to at least two other nodes.

Another observation is that the plugs are the only devices that will occasionally flash when viewing the z2m map. Assuming I have some defective units, I’ve replaced one with a new one to see if the issue reoccurs.

Anyway the significant other is very unhappy when things only work some of the time…


The plug has failed again and I switch back to some spare Kasa plugs. I do not recommend these!!!


I have two of these plugs and they go “Unavailable” all the time. I’m going to look for other zigbee plugs.


I haven’t had issues with the Sonoff S40 I got to test, but my go to plug us still the Sengled E1C-NB7. Amazon has a coupon offer right now on the 4 pack. About $10 per plug before tax.

Normal price is a good bit higher, but the promos come along fairly often.

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