A Bluetooth USB adapter is not special from the virtualization layer's point of view: first the ZimaOS host must enumerate the USB device, then the VM must receive that host device through passthrough. If the host cannot see it, there is nothing for the guest to claim.
Separate Host Detection from Guest Passthrough
Start by checking whether the USB adapter exists on the host. If the device is visible there but missing inside the VM, move to the ZVM/libvirt assignment layer. If it is absent on the host, changing Home Assistant settings inside the guest will not fix it.
USB Passthrough Gives the Device to One Guest
The upstream libvirt host device passthrough documents host-device passthrough and notes that a passthrough device cannot be simultaneously used by the host and an active guest. That matters for Bluetooth and radio dongles because the guest normally needs exclusive access while the VM is running.
The virtual machine requirements provides current ZimaOS virtualization and passthrough context, while the Home Assistant VM setup specifically explains why Zigbee, Z-Wave, and USB radios need to be passed into a Home Assistant OS VM.
Home Assistant Container and HAOS VM Are Different
The Home Assistant requirements distinguishes a Home Assistant Container deployment from HAOS. In a container, hardware is mapped into Docker; in a VM, the USB device must be assigned through the virtualization layer. The two procedures are not interchangeable.
Home Assistant's Home Assistant VM options documents VM-based installation paths separately from container installs, which is why you should first confirm which Home Assistant installation type you actually run.
A Practical Troubleshooting Order
- Confirm the USB Bluetooth adapter is visible on the ZimaOS host.
- Shut down the target VM before changing device assignment if the interface requires it.
- Add the correct USB host device to the VM rather than relying only on a generic USB controller.
- Start the VM and verify the adapter inside the guest.
- If it disappears after reboot, re-check whether the host identifier changed or whether the device was claimed elsewhere.
Bottom Line
For a Home Assistant VM, treat the Bluetooth dongle as a USB passthrough device. Host detection must work first, then ZVM/libvirt must assign the device to the guest, and only then can Home Assistant use it. There is no evidence in the source thread of a separate ZimaOS “enable Bluetooth” switch.
