Sonoff Dongle M unable to pair

[lettore]

Before opening another issue on this matter... the previous one didn't make any progress, I would like to try to see if anyone else had the same issue. I built my Zigbee network on a Sonoff Dongle E in the past, and as I wished a HA setup I needed a LAN coordinator not tied to a single machine. I did all the steps to migrate to the Sonoff Dongle M, without the need to re-pair every device, and everything worked as expected, also very stable and fast operation on the network. The issue is related to pairing. I can't literally be able to pair any new devices; they pair, discover, they send and receive signals for just 15-20 sec and then they leave the network, and the cycle goes on forever like that. I tried many devices, some of the same model I already have in my network, but none of them works. Battery powered, mains powered, doesn't matter. It seems to me that zigbee2mqtt or the coordinator doesn't send the pairing key to the device, at least is what I assume.
PS the issue seems to happen on all the cheap zigbee devices from China, seen like Tuya devices.
Even enabling debug logging doesn't show me any key message just this

[17/05/2026, 12:28:24] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":'{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_leave"}
[17/05/2026, 12:28:36] z2m: Accepting joining not in blocklist device '0xa4c13817c9035080'
[17/05/2026, 12:28:36] zh:controller: Interview for '0xa4c13817c9035080' started
[17/05/2026, 12:28:36] z2m: Device '0xa4c13817c9035080' joined
[17/05/2026, 12:28:36] z2m: Starting interview of '0xa4c13817c9035080'
[17/05/2026, 12:28:36] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_joined"}'
[17/05/2026, 12:28:36] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080","status":"started"},"type":"device_interview"}'
[17/05/2026, 12:28:36] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_announce"}'
[17/05/2026, 12:28:37] zh:controller: Succesfully interviewed '0xa4c13817c9035080'
[17/05/2026, 12:28:37] z2m: Successfully interviewed '0xa4c13817c9035080', device has successfully been paired
[17/05/2026, 12:28:37] z2m: Device '0xa4c13817c9035080' is supported, identified as: Tuya Temperature and humidity sensor (ZTH05_1)
[17/05/2026, 12:28:37] z2m: Configuring '0xa4c13817c9035080'
[17/05/2026, 12:28:37] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"definition":{"description":"Temperature and humidity sensor","exposes":[{"access":1,"category":"diagnostic","description":"Remaining battery in %, can take up to 24 hours before reported","label":"Battery","name":"battery","property":"battery","type":"numeric","unit":"%","value_max":100,"value_min":0},{"access":1,"description":"Measured temperature value","label":"Temperature","name":"temperature","property":"temperature","type":"numeric","unit":"°C"},{"access":1,"description":"Measured relative humidity","label":"Humidity","name":"humidity","property":"humidity","type":"numeric","unit":"%"},{"access":1,"category":"diagnostic","description":"Voltage of the battery in millivolts","label":"Voltage","name":"voltage","property":"voltage","type":"numeric","unit":"mV"},{"access":1,"category":"diagnostic","description":"Link quality (signal strength)","label":"Linkquality","name":"linkquality","property":"linkquality","type":"numeric","unit":"lqi","value_max":255,"value_min":0}],"model":"ZTH05_1","options":[{"access":2,"description":"Calibrates the temperature value (absolute offset), takes into effect on next report of device.","label":"Temperature calibration","name":"temperature_calibration","property":"temperature_calibration","type":"numeric","value_step":0.1},{"access":2,"description":"Number of digits after decimal point for temperature, takes into effect on next report of device. This option can only decrease the precision, not increase it.","label":"Temperature precision","name":"temperature_precision","property":"temperature_precision","type":"numeric","value_max":3,"value_min":0},{"access":2,"description":"Calibrates the humidity value (absolute offset), takes into effect on next report of device.","label":"Humidity calibration","name":"humidity_calibration","property":"humidity_calibration","type":"numeric","value_step":0.1},{"access":2,"description":"Number of digits after decimal point for humidity, takes into effect on next report of device. This option can only decrease the precision, not increase it.","label":"Humidity precision","name":"humidity_precision","property":"humidity_precision","type":"numeric","value_max":3,"value_min":0}],"source":"native","supports_ota":true,"vendor":"Tuya","version":"0.0.0"},"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080","status":"successful","supported":true},"type":"device_interview"}'
[17/05/2026, 12:28:38] z2m: Successfully configured '0xa4c13817c9035080' (definition v0.0.0)
[17/05/2026, 12:28:46] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":40225,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":39,"linkquality":104,"temperature":25,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:28:46] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":40225,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":36,"linkquality":104,"temperature":25,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:28:57] z2m: Device '0xa4c13817c9035080' left the network
[17/05/2026, 12:28:58] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_leave"}'
[17/05/2026, 12:29:04] z2m: Accepting joining not in blocklist device '0xa4c13817c9035080'
[17/05/2026, 12:29:04] zh:controller: Interview for '0xa4c13817c9035080' started
[17/05/2026, 12:29:04] z2m: Device '0xa4c13817c9035080' joined
[17/05/2026, 12:29:04] z2m: Starting interview of '0xa4c13817c9035080'
[17/05/2026, 12:29:04] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_joined"}'
[17/05/2026, 12:29:04] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080","status":"started"},"type":"device_interview"}'
[17/05/2026, 12:29:04] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/health', payload '{"response_time":1779013744997,"os":{"load_average":[0.94,1.84,2.81],"memory_used_mb":14484.99,"memory_percent":91.2128},"process":{"uptime_sec":1205,"memory_used_mb":148.46,"memory_percent":0.9349},"mqtt":{"connected":true,"queued":0,"published":1396,"received":693},"devices":{"0xa81710b8114b0000":{"messages":4,"messages_per_sec":0.0033,"leave_count":0,"network_address_changes":0},"0xa4c138a0a3c49520":{"messages":67,"messages_per_sec":0.0559,"leave_count":0,"network_address_changes":0},"0x0017880104e1c655":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x001788010382440a":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x0017880104e1bfdb":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x00158d0000aee0aa":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x0017880104e29f40":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x00178801035e6a66":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0x00178801026e5716":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0xf0d1b8000010c304":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0xf0d1b8000010c65b":{"messages":3,"messages_per_sec":0.0025,"leave_count":0,"network_address_changes":0},"0xa4c13817c9035080":{"messages":51,"messages_per_sec":0.0433,"leave_count":6,"network_address_changes":0},"0xf0d1b8000010c69b":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0xf0d1b8000010c697":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0x7cb03eaa00ac2ce0":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0x90fd9ffffe2a571a":{"messages":4,"messages_per_sec":0.0034,"leave_count":0,"network_address_changes":0},"0x00158d0000b12a38":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0x00158d00013119c7":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0x00178801026e5488":{"messages":3,"messages_per_sec":0.0026,"leave_count":0,"network_address_changes":0},"0x70b3d52b60030670":{"messages":42,"messages_per_sec":0.0366,"leave_count":0,"network_address_changes":0},"0xe0798dfffeb31b38":{"messages":11,"messages_per_sec":0.0102,"leave_count":0,"network_address_changes":0},"0x000b57fffe59e69d":{"messages":8,"messages_per_sec":0.0078,"leave_count":0,"network_address_changes":0},"0x00158d0004025f35":{"messages":1,"messages_per_sec":0.0011,"leave_count":0,"network_address_changes":0},"0x7cb94c78320a0000":{"messages":6,"messages_per_sec":0.0083,"leave_count":0,"network_address_changes":0},"0xb40ecfd177e60000":{"messages":6,"messages_per_sec":0.0088,"leave_count":0,"network_address_changes":0},"0x7cb94c7833600000":{"messages":6,"messages_per_sec":0.0088,"leave_count":0,"network_address_changes":0},"0x00158d000393690c":{"messages":2,"messages_per_sec":0.0032,"leave_count":0,"network_address_changes":0},"0x001788010408dc7d":{"messages":1,"messages_per_sec":0.0016,"leave_count":0,"network_address_changes":0},"0x00158d0004200b7d":{"messages":6,"messages_per_sec":0.0099,"leave_count":0,"network_address_changes":0},"0xa4c13889baecef58":{"messages":3,"messages_per_sec":0.0054,"leave_count":0,"network_address_changes":0},"0xa4c138d90c9fceb2":{"messages":76,"messages_per_sec":0.1902,"leave_count":9,"network_address_changes":0},"0x00158d00045cd385":{"messages":1,"messages_per_sec":0.0043,"leave_count":0,"network_address_changes":0},"0x00158d000213249c":{"messages":1,"messages_per_sec":0.0346,"leave_count":0,"network_address_changes":0}}}'
[17/05/2026, 12:29:05] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080"},"type":"device_announce"}'
[17/05/2026, 12:29:06] zh:controller: Succesfully interviewed '0xa4c13817c9035080'
[17/05/2026, 12:29:06] z2m: Successfully interviewed '0xa4c13817c9035080', device has successfully been paired
[17/05/2026, 12:29:06] z2m: Device '0xa4c13817c9035080' is supported, identified as: Tuya Temperature and humidity sensor (ZTH05_1)
[17/05/2026, 12:29:06] z2m: Configuring '0xa4c13817c9035080'
[17/05/2026, 12:29:06] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/bridge/event', payload '{"data":{"definition":{"description":"Temperature and humidity sensor","exposes":[{"access":1,"category":"diagnostic","description":"Remaining battery in %, can take up to 24 hours before reported","label":"Battery","name":"battery","property":"battery","type":"numeric","unit":"%","value_max":100,"value_min":0},{"access":1,"description":"Measured temperature value","label":"Temperature","name":"temperature","property":"temperature","type":"numeric","unit":"°C"},{"access":1,"description":"Measured relative humidity","label":"Humidity","name":"humidity","property":"humidity","type":"numeric","unit":"%"},{"access":1,"category":"diagnostic","description":"Voltage of the battery in millivolts","label":"Voltage","name":"voltage","property":"voltage","type":"numeric","unit":"mV"},{"access":1,"category":"diagnostic","description":"Link quality (signal strength)","label":"Linkquality","name":"linkquality","property":"linkquality","type":"numeric","unit":"lqi","value_max":255,"value_min":0}],"model":"ZTH05_1","options":[{"access":2,"description":"Calibrates the temperature value (absolute offset), takes into effect on next report of device.","label":"Temperature calibration","name":"temperature_calibration","property":"temperature_calibration","type":"numeric","value_step":0.1},{"access":2,"description":"Number of digits after decimal point for temperature, takes into effect on next report of device. This option can only decrease the precision, not increase it.","label":"Temperature precision","name":"temperature_precision","property":"temperature_precision","type":"numeric","value_max":3,"value_min":0},{"access":2,"description":"Calibrates the humidity value (absolute offset), takes into effect on next report of device.","label":"Humidity calibration","name":"humidity_calibration","property":"humidity_calibration","type":"numeric","value_step":0.1},{"access":2,"description":"Number of digits after decimal point for humidity, takes into effect on next report of device. This option can only decrease the precision, not increase it.","label":"Humidity precision","name":"humidity_precision","property":"humidity_precision","type":"numeric","value_max":3,"value_min":0}],"source":"native","supports_ota":true,"vendor":"Tuya","version":"0.0.0"},"friendly_name":"0xa4c13817c9035080","ieee_address":"0xa4c13817c9035080","status":"successful","supported":true},"type":"device_interview"}'
[17/05/2026, 12:29:06] z2m: Successfully configured '0xa4c13817c9035080' (definition v0.0.0)
[17/05/2026, 12:29:11] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":24725,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":36,"linkquality":104,"temperature":25,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:29:11] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":24725,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":34,"linkquality":120,"temperature":25,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:29:17] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":24725,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":34,"linkquality":112,"temperature":24.9,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:29:18] z2m:mqtt: MQTT publish: topic 'zigbee2mqtt/0xa4c13817c9035080', payload '{"battery":100,"device":{"applicationVersion":64,"dateCode":"","friendlyName":"0xa4c13817c9035080","hardwareVersion":1,"ieeeAddr":"0xa4c13817c9035080","manufacturerID":4417,"manufacturerName":"_TZ3000_bgsigers","model":"ZTH05_1","networkAddress":24725,"powerSource":"Battery","stackVersion":0,"type":"EndDevice","zclVersion":3},"humidity":33,"linkquality":104,"temperature":24.9,"update":{"installed_version":-1,"latest_version":-1,"state":null},"voltage":3000}'
[17/05/2026, 12:29:18] z2m: Device '0xa4c13817c9035080' left the network

[andrei-lazarov]

Yeah, same issue reported here:

• [SLZB-06M] TCP bug: Sensors drop after 20s - Support ignores logs and suggests return for functional hardware #30455 (comment)

I believe the coordinator is in a bugged state from the migration. You probably need to clear its memory, or start over, re-pair everything...

If the coordinator was not bugged, these would be my generic pairing tips:

Details

Improve network conditions and try pairing again:

• Update coordinator firmware
• Use a modern and well-supported coordinator
• Try latest Z2M (switch to dev branch)
• Check Health tab for spammy devices
• Bring device closer to coordinator
• Pair directly through the coordinator (or try other devices, use drop-down on Permit join)
• Power-off 'bad' routers (e.g. Telink Tuya, AwoX)
• Add USB 2.0 extension cable to dongle coordinators (avoid USB interference)
• Change Zigbee channel (avoid radio interference - if possible, stick to the defaults: 11, 15, 20, 25)
• Increase coordinator transmit_power in Z2M
• Pair another device at the same time
• Use manufacturer-recommended batteries (fresh Alkalines / full rechargeables)

It may also help to restart Z2M between pairing attempts

[lettore]

I can give you a feedback on what I did:
1 - Sonoff Dongle M (EFR32MG24) connected via TCP with any kind of Firmware version, up to 8.0.2 -> pairing fails after 20 sec there's a leave
2 - Sonoff Dongle M (EFR32MG24) connected via USB with local serial /dev/serial/*** -> pairing fails after 20 sec there's a leave
3 - Sonoff Dongle E (EFR32MG21) connected via USB with local serial /dev/serial/*** -> pairing works immediately
Now there's something to say, both adapters have the same IEEE address, but as I switched from Dongle E to Dongle M the IEEE address of the Dongle E is the primary, while the IEEE address of the Dongle M is secondary. It's hard to believe that there's such a bug in the firmware to prevent even the pairing.... so I guess the issue is related to having 2 IEEE addresses? Or something get stuck in the memory of the Dongle M after the IEEE change? I will try to flash clear the dongle M and upload again the firmware and see if works. But in the other discussion they pointed to the TCP connection the issue, but as even in serial mode the adapter fails to pair with anything it means is something more deeper than just connection.

[andrei-lazarov]

@Nerivec if you can help with those migrations 😭

[Nerivec]

Would need debug log level to be able to see the actual exchanges (including possible keys).

Here's what you can check/try:

• Unplug the old adapter before you start the new one
• Make sure the IEEE didn't get reversed by mistake during migration. (e.g. ...2211 instead of 1122...).
• Use ember-zli to ensure you weren't affected by a nasty bug; the prompt will tell you if you are or not: https://github.com/Nerivec/ember-zli/wiki/Stack#check-for-eui64-mismatch
• Clear the NVM of the new adapter (basically a reset to factory default), then re-do the IEEE migration, then let Z2M startup, which will force the network to restore from your last backup.
• If the issue persists, re-try previous step, but do not do the IEEE migration, and instead try running the network from the clean adapter (post NVM clear). In a lot of cases, devices adapt on their own; though you may need to re-pair a few less adaptable ones.

---

Note: the mentioned previous issue was filled with incorrect AI-driven "analysis"/assumptions.