I just updated to the latest build on one of my two working P110s. It is now showing 1.1.2 Build 220930 Rel. 144500. For now it is still working fine.

Ok, another update. I have 7 TP-Link Tapo P110s. All working fine for several weeks until something changed on my ASUS wifi access point. (All other wifi devices in the house working fine, though.)

 

I am going to start using letters to name my TP-Link devices for consistency in future.

 

The two working devices:

* Device D: never stopped working. Was originally running firmware X and yesterday I manually updated to 1.1.2. It continues to work perfectly. Signal icon shows 1 bar.

 

* Device F: never stopped working. Is still on firmware 1.0.7 and I have turned off automatic updates. It continues to work perfectly. Signal icon shows 2 bars.

 

* Device G: did not reconnect after I fixed my wifi AP. Reconnected when I re-paried it. Disconnected after firmware update to 1.1.2. Works for hours at a time but randomly disconnects (showing red light). If I un-plug and plug back in, it immediately reconnects. Signal icon shows 2 bars (it's in the same room as the AP, fwiw).

 

* Device C: did not reconnect after I fixed my wifi AP. Has not reconnected since despite several attempts to re-pair including in the room with the wifi AP.

 

* Device W: the same as device C.

 

* Devices E and S: these behaved like device G but they are currently disconnected and it would be inconvenient to power cycle them right now. Without power cycling I suspect the only way to re-connect will be to re-pair and that is also annoying.

 

I would like to help debug these issues. I do not understand why behaviour is so different between different devices. They are all the same model as far as I can see. I am a software developer and I would be happy to run experiments with diagnostic tools.

EDIT: Devices D and F have now disconnected. These were the two devices that had previously worked reliably throughout. Device E has also disconnected. G, W and S are still connected for now (this is an hour after making these changes).

Another update.

 

I think I may have found a workaround. Annoyingly I changed three things before checking whether the situation had changed, but I have a good guess about which one made the difference.

 

1. Updated my ASUS RT-AC3200 to firmware version 3.0.0.4.382_52651 (but this was a minor point update)

 

2. Under Wireless, Professional, set Airtime Fairness to "disable". Though checking now, this only seems to be disabled for the 5GHz-2 radio, which might even be the default, so I don't think I actually changed anything relevant here.

 

3. Under Network Tools, Smart Connect Rule, for the 2.4GHz radio, under Band Steering Condtion, set VHT to AC Only. According to the article "ASUS RT-AC3200 Smart Connect: The Missing Manual" on smallnetbuilder dot com, this means that only devices that support AC wifi will trigger band steering. Since devices should always first connect on 2.4GHz, this means that non-AC devices will only connect on 2.4GHz. It is my guess that the P110 smart plugs don't support AC wifi and as a result of this setting do not get band-steered, and that this somehow fixes the problem.

 

I say "somehow", because I don't understand why a device that does not support 5GHz would respond to a steer onto a 5GHz band, but that may be what's going on as a result of some bug.

 

So far so good but it's only been an hour or so (but before 3 of my devices would not connect at all). Will update if it turns out this is not reliable.

For now I have turned off band steering for 2.4GHz (I now have Smart Connect set to "5GHz Smart Connect") and since then everything has been fine.