UPDATE: TP-Link have provided me updated firmware that significantly reduces the extraneous messages when the switch is OFF but does not remove them when the switch is ON. They are still working on it.

  @BrianMal 

Just installed a couple of these switches and I'm seeing the same issue.  Did they give you the impression that this was something they could fix?

  @Amuzing 

When I first installed these switches, they would blink and send messages several times a minute when OFF and every hour or so when ON. I contacted TP-Link and, a couple od days later, they provided new firmware that fixed 99% of the OFF messages but did not address the rarer ON messages. I just received a second update in the last hour which I have just finished installing but since the ON messages are rarer, I will not know until tomorrow morning if they are fixed. However, if you use the Tapo App to update the firmware, this newer version is the one you should get. The version is 1.0.4 Build 250124 Rel.181840

FYI: My Home Assistant did not find the switch after I installed the new firmware and I had to delete it and re-add it.

Brian

  @BrianMal 

Sounds good.  I filed a ticket for this issue as well. If/when they send me a fw update to try, I'll run the same test with Home Assistant and report back.

  @Amuzing 

No luck. The new firmware did not help the issue. I have notified them. 

FYI. It looks like TP-link is located in Hong Kong area and will probably be off for a few days for Chinese New Year.

Brian 

  @BrianMal 

Just an update. 

The same updated FW version you mentioned above was pushed to my two S515 switches.  I have them set up in Home Assistant and will keep an eye on the log messages.

Mark

 @BrianMal 

Since the new firmware was pushed, I haven't seen any issues with the status LED.  Home Assistant is not showing any change of state messages in the logbook either.  The switch was ON for half of the day, and OFF the other half.

One thing I noticed is that the status messages seems to be generated based on the current draw, not the switch positions.  I guess this is the easiest way to do it since the switch can be wired as single pole, 3 and 4-way.  You can test this out by turning the light ON and unscrewing it from the socket.  In my 3-way configuration, it will send a status message without the remote switch being flipped or the S515 relay changing state when the bulb is either removed or replaced.

If that's the case, it's possible that anything affecting the current draw could trigger a status meesage (wiring, bulb, conacts in the socket if it's an actual bulb, brown-outs, etc.).  Just speculating here.

Anyways, I'll continue to keep an eye on the logs over the weekend and will update on Monday.
 

  @Amuzing 

Thanks for info.

I am currently running 3 small bulbs in outdoor sconces that draw about 4 watts total, pretty low. I get OFF/ON messages about once an hour at night when the lights are on. I will try your test and also try with a higher wattage bulb.

  @BrianMal 

Low wattage could be an issue as well.

I also noticed that there is about a 3 second delay in reporting a status change when either the remote switch is flipped, or the S515 button is pushed (filtering? settling time?).

If you switch the light ON -> OFF or OFF -> ON from either switch within that time, no status message is generated for either event.