We are not neglecting the issue, but with the current hardware this is the best we can achieve. We are planning redesign and replacement of the power metering chip.
So where we can return this units with random generators? I've bought 4 1PM Plus units and becouse of this issue two of them never came out of the boxes, replaced by gen 1 units..... When one buys an unit with Power Meter in the name it should work at least as Power Meter not a random number generator.
The latest update has helped on the "voltage spikes" but hasn't helped on the values 
Every other Shelly except the two Shelly Plus 1PM shows 244V, but at least now it's evenly underrated with no spikes
Now is eve worse - Voltage in Web UI jumping from 214V to 228V (always this two values)
Installed 0.11. 2 beta 1 - still same issue.
What is ETA for fix this issue?
I have 2 new 1 Plus PM and both are showing strange values, one is similiar to Your problem it jumps from 214 to 221, other one shows 245Vpm1.png
but all of 2.5 and all other devices shows consistently 240-241...
Yup,
Tried, newest, oldest...
http://192.168.33.1/ota?url=http:/…PLG-S_build.zip
http://192.168.33.1/ota?url=http:/…PLG-S_build.zip
but I can't see how it could work when device is not connecting to wifi with internet...
after connecting via app, I checked wifi settings and there was this:
"wifi_sta": {
"enabled": false,
"ssid": "MotylkowoCzerwono",
"ipv4_method": "dhcp",
"ip": null,
"gw": null,
"mask": null,
"dns": null
}
currently I'm trying to switch this on via rest API, but with no success ;/
Huuray, the trick with local webserver and updating to newest firmware via: http://192.168.33.1/ota?url=http:/…LG-S_build2.zip worked!!!! Oldest came with same json as before.
Now it seems to work, propertly, got the IP address, I've changed setting, switch on/off wokrs, it measures power...
Thank You all for clues and help 
Which request ?
tried to POST this, but it seems it's made in other way... I'm reading documentation ...
My other idea is to start webserver on my laptop and put the 192.168.33.2 host for ota and firmware update.
Have you tried an update via the firmware archive?
Yup,
Tried, newest, oldest...
http://192.168.33.1/ota?url=http://archive.shelly-support.eu/v1.5.10/SHPLG-S_build.zip
http://192.168.33.1/ota?url=http://archive.shelly-support.eu/v1.12/SHPLG-S_build.zip
but I can't see how it could work when device is not connecting to wifi with internet...
after connecting via app, I checked wifi settings and there was this:
"wifi_sta": {
"enabled": false,
"ssid": "MotylkowoCzerwono",
"ipv4_method": "dhcp",
"ip": null,
"gw": null,
"mask": null,
"dns": null
}
currently I'm trying to switch this on via rest API, but with no success ;/
I can't read your instructions because he wants me to register.
but here is a link, it had helped someone else.
there are two different things explained, so please read all the comments.
Yes, I tried everything from this, I assume that this is the problem (instructions are for 1PM):
2. Press reset button on the back shortly
3. Device will boot and will leave from this mode temporary.
There is no reset button on Shelly Plug S, reset is done by pressing 10s. I tried to push on/off button shortly, also presing it >10s... nothing seems to tell the Shelly Plug S to exit this mode temporary ;/ If I try to include it by app, app finds the devace, when I click include, app is waiting for "Pending Connection" forever, also tried to see if it connected to my router just for any other of my shelly devices, but no, it don't connects. I'm stuck with it ;/
Try to remove the s from https:// to http:// in your adressbar
Never added the s in address. "Niezabezpieczona" means unprotected.
One of my new Shelly Plug S Devices after booting seems to be in factory test mode. Tried to figure it out with this instructions
https://www.facebook.com/legacy/notes/2092489927517027/
but it does not work, as I think this is instruction for other shelly devices. Anyone know how to exit this mode in Shelly Plug S?
