Alpha 864s' Bluetooth driver

Hi everyone,  

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I installed Windows 10 Pro from scratch. Although an Intel Bluetooth driver was loaded by the Microsoft Driver Support Assistant, the Bluetooth performance is rather poor. When using a COULAX Bt 4.1 headset with AirPods 1. Gen Bt 4.2, a Bluetooth headset connected right in front of the Alpha exhibits something of an on-off behavior.

Is the antenna or the driver at fault here? Is using an external M.2 Broadcom card beneficial? Which one, if any, should I purchase?