I own a Mi Max 3 (nitrogen) on the xiaomi.eu build 8.11.15.
I discovered this fix while doing a search on an adb logcat entry that happened whilst the Bluetooth issue was happening on my device.
You will need ROOT access to edit the buildprop file.
The two lines below appeared in logcat as I...
I recently purchased a Mi Max 3 from a reseller of Mi phones (probably imports them from China then resells on)
Anyways, it's the 128GB 6GB edition that was released in November.
It came pre-installed with MIUI9 China (9.6.12).
I checked for ARB and it results in - getvar:anti FAILED...