Noble Stops Receiving Advertisements

Hi,

First off, I appreciate this is an issue with Noble rather than Espruino/Pucks but I thought asking here might be more fruitful than raising an issue on GitHub as someone may have similar experience.

I have several Pis setup around the house as satellites for an unrelated project and a Pi 4 as a master device on my entertainment unit. The case I'm using for the Pi 4 does a cracking job of nullifying the Bluetooth signal... Therefore, I set up a relay script of sorts that runs on some of the satellite devices picking up the advertiserments of the Pucks I have around the home using Abandonware/Noble, and they feed into the master device over Wifi.

Several weeks ago I did a fresh install of, what is now Raspberry Pi OS on a Pi3 located in my conservatory. After a period of time, several hours, 1 day, 2 days, but no more than 3 days the Pi stops "receiving" the advertisements. Noble reports no state change, there's no errors and no advertisements. Nothing. As soon as I restart the script, Noble reconnects and all works again.

My script is stored on a NAS and is used by all of the satellites with no problems whatsoever. Any other satellite and it wouldn't be an issue, but typically this particular Pi is picking up a Puck that no other Pi can reliably receive.

Has anyone has similar issues using Abandonware/Noble or EspurinoHub (as I believe that uses Noble too) recently? My feeling is it's driver related... I'm not sure what I can check, or what I should look for to help diagnose.

One thing that might help is stopping the system Bluetooth (sudo /etc/init.d/bluetooth stop). I think what can happen is the system starts its own scan for available Bluetooth devices, then stop scanning when it's finished, which stops Noble's scan.

You could also try handling the scanStop event and using it to start scanning again? https://github.com/noble/noble/blob/master/README.md#scan-stopped

Thanks for your thoughts Gordon.

I should have been clearer when I said there's no change to state. I added handles for stateChange and scanStop to write to a log because that too was my first thought. However, as said, nothing.

Connected
Starting scan...
State change: poweredOn
Scanning started.
**RESTARTED**
Connected
etc.

That's a shame - in EspruinoHub we actually detect if no advertising data has been received for a while and restart if not. You could do that?

It might work just to try calling startScanning again if no advertising has been received for a while?