Question about ASUS Usb-Bt400

Ok, I treated myself to the part. Works 1A and without the slightest problem under Linux. Plug it in, pair it, it works!

I only have Linux on my server. I got the stick to work under Windows 7 with a Jaybird headphone. It shouldn't be the hardware. I don't use it anymore after I bought a motherboard with integrated BT from Intel.
Unlike cheap competitor products that use an outdated BT chipset from a defunct manufacturer, this stick runs on a Broadcom chipset.
Regarding Linux drivers, you can check yourself. The PCI Id is: VID_0B05 & PID_17CB
In my experience it is not the Hw driver that is the problem, but the newer BT profiles. To get good audio quality on the headphones, you need the latest generation profiles. Even under Windows, these do not come from Microsoft, but must be supplied by the manufacturer in the driver package.