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Noise sensor always on 99dB

Hi there,

I’ve just launched my kit some weeks ago and I’ve noticed that it’s been stuck at 99dB, although I’ve changed its location to check if this would vary.

Also, barometric pressure doesn’t seem to change much.

Light is at 0 lux despite we are now at daylight.

Could my kit be broken?

Thanks a lot,


Dear @doktorkampi,

Thanks for posting! I’ll try to answer step by step:

We have had this issue with some devices exposed to high humidity conditions, and in other cases, with a hardware problem. In the first case, the microphone comes back to life after a little while, but not in the second. So if it persists, the best is to email for hardware problems

This one won’t change much, since the normal atmospheric pressure is always around 101kPa next to sea level, except when there’s a storm coming or a heat wave. Generally, lower barometric pressures indicate a storm, and the opposite for the heat.

Regarding this, there is a firmware issue that has been fixed as explained here.

Dear @oscgonfer,

Thanks a lot for your kind reply. I will ask the Seeed support team, as the problem persists despite the humidity variations during the last weeks.

As for the barometric pressure, thanks for the info.

Regarding the light sensor and the firmware, I read the post but I didn’t get if the firmware update is going to be automatic or should I be the one to update it. It clearly still not working for me (now it’s night-time and the sensor indicates 2k lux).

Again, thanks for your help.



OK, let us know if we can be of any help.

You have to perform the firmware update. This is quite simple and documented in the post here or in the docs. Let us know if you have any issue.


Hi @oscgonfer,

The Seeed support team referred me directly to the SmartCitizen support team. :man_shrugging:

I updated the firmware and I used the same token I already had for the onboarding process, but the kit profile is not getting any new data ( Any idea on what could be wrong? I don’t know if the light sensor problem has been solved, for I am not receiving any new data (the kit seems to be working properly and sending data: the blue led is beeping slowly).

Thanks for your help,


Hi @doktorkampi

First, what the led is? Is it breathing slowly or blinking fast?

I will suggest you try to reboot the Kit by pressing the reset button:

You can always press the on/off button one time for the led to turn red and set your Kit on setup mode. Then you can connect to the SmartCitizen[...] Wi-Fi again to check your token, and network setting are ok.

Hope it helps!

Hi @pral2a!

The blink is slow (it should be sending data). I tried to reset the kit, still no data online.
I set the kit on setup mode and I checked the token and the WiFi.

The WiFi seems to be working properly. Could the token be wrong and the kit may be sending data to a different kit profile? Maybe I misspelled the token when I updated the firmware. Is there a way to find out my former token?

Thanks a lot,



I just sent you your token in a message.
Please try to factory reset your kit and configure it again.

If this doesn’t fix the problem maybe you can check the debug messages of your kit with the SCK shell and try to get more information.

Hope this helps!


Thanks a lot!!!
I misspelled the token, now is sending data online.

The noise sensor seemed to be stuck, but then I followed your advice about SCK shell. I found no interesting debug messages. I tried “monitor Noise” and suddenly it started to give real noise data. No idea about what really happened.


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Again stuck at 99db… I think it is not something hardware-related, because it worked when I had it monitored and USB connected.

Now I am totally lost. I wasn’t receiving the data the kit was sending, even though the token and the WiFi setup were OK. I couldn’t read the shell with Arduino as I did before. So I decided to factory-reset it, but nothing. I tried twice or three times, but still nothing. I hear the PM sensor working, the led lights seem fine (blue led smoothly and softly blinking).

I contacted with the Seeed staff and they will be sending me a new one as soon as they have in stock.

Any idea on how to revive it?


I don’t know how but it started to work again…

Hi @doktorkampi,

Sorry for our silence with this. How come it had revived? Is it now working?
We are looking at the 99dB problem on our side as well, we will come back with our findings.



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I don’t really know how it worked out. I started to have the kit permantly connected to a power supply (after experimenting with a solar pannel that didn’t work quite well). I still see some moments when the kit remain at 99dB (which I understand is the maximum value it can get).

Thanks a lot,


Hi @doktorkampi,

We are looking into it with some test SCKs. Probably there is an issue with the power supply noise, but we are not sure. We will keep you posted with our findings.

Let us know if you see this happening again and try to note if anything has changed (high humidity, temperature, rain, power supply change… etc.)



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Check out the tests here:

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It’s the same that happens with my sensor, but with mine this happens even though there is no rain or any kind of liquid whatsoever.

Is it possible to purchase the enclosure+foam or at least the enclosure?


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