Bluetooth is dying every now and then

Configuration
1

Since recently, every few days, my bluetooth is dying which breaks some of my automations that rely on a bt outside temperature sensor.

There’s a warning in the log

Logger: bluetooth_auto_recovery.recover
Source: runner.py:280
First occurred: September 20, 2026 at 23:40:45 (4326 occurrences)
Last logged: 08:41:16

There are no BT controllers present in the system!
Could not find adapter with mac address 00:15:83:E9:6F:71 or hci0

immediatley followed by this error

Logger: habluetooth.scanner
Source: /usr/local/lib/python3.14/asyncio/events.py:94
First occurred: September 20, 2026 at 23:40:45 (1082 occurrences)
Last logged: 08:41:16

hci0 (00:15:83:E9:6F:71): Failed to restart Bluetooth scanner
Traceback (most recent call last):
  File "src/habluetooth/scanner_bleak.py", line 447, in habluetooth.scanner_bleak.HaScanner._async_start_attempt
  File "src/habluetooth/scanner_bleak.py", line 448, in habluetooth.scanner_bleak.HaScanner._async_start_attempt
  File "src/habluetooth/scanner_bleak.py", line 450, in habluetooth.scanner_bleak.HaScanner._async_start_attempt
  File "/usr/local/lib/python3.14/site-packages/bleak/__init__.py", line 185, in start
    await self._backend.start()
  File "/usr/local/lib/python3.14/site-packages/bleak/backends/bluezdbus/scanner.py", line 124, in start
    self._stop = await manager.passive_scan(
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ...<4 lines>...
    )
    ^
  File "/usr/local/lib/python3.14/site-packages/bleak/backends/bluezdbus/manager.py", line 560, in passive_scan
    self._check_adapter(adapter_path)
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.14/site-packages/bleak/backends/bluezdbus/manager.py", line 209, in _check_adapter
    raise BleakError(f"adapter '{adapter_path.split('/')[-1]}' not found")
bleak.exc.BleakError: adapter 'hci0' not found

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "src/habluetooth/scanner_bleak.py", line 679, in habluetooth.scanner_bleak.HaScanner._async_restart_scanner
  File "src/habluetooth/scanner_bleak.py", line 368, in _async_start
  File "src/habluetooth/scanner_bleak.py", line 499, in _async_start_attempt
habluetooth.scanner_bleak.ScannerStartError: hci0 (00:15:83:E9:6F:71): Failed to start Bluetooth: adapter 'hci0' not found; Try power cycling the Bluetooth hardware.

I then need to power cycle the bt adapter. What could be the issue here? I’m running HA on Proxmox with passthrough. There’s also a zigbee stick and a rtl433 stick with pass though. Neither of them has a connection problem.

2

Are you using a bluetooth adapter that is on the known to work list? Bluetooth - Home Assistant

3

yes, it’s this one: Avantree BTDG-40S (CSR8510A10)

4

Is your operating system version perhaps outdated? I ask because I recall having Bluetooth issues with versions 13 or 14, but since upgrading to 15.2, Bluetooth has been rock-solid. So, I’d say version 15.2 is a safe minimum for Bluetooth, especially passive mode and BT proxy.

5

I’m currently on HAOS 18.2 with this issue

version info:

* Installation method Home Assistant OS
* Core 2026.9.2
* Supervisor 2026.09.2
* Operating System 18.2
* Frontend 20260826.7
6

Another possible cause is an underpowered PC. Again, from my personal experience: I run HA on a low-power thin client, and after adding an USB drive, another device (an RTL dongle) would occasionally drop out of the system. The solution in this case was to connect the drive using an enclosure with its own power supply.

7

Unlikely. In running an Esprimo D958. No external hdds or anything, just three dongles. The pc itself has 10 usb ports, so should be far from the limit

8

Hmm, it was running stable for over two weeks now. Today, again it lost connection. It’s very rare, but super annoying. I changed usb port and extension cord now. Will see if that helps. Otherwise, I’ll probably use an ESP32 as proxy..

9

That didn’t help. It only worked for around 12h before breaking down again..