Bluetooth headphone does not work in Fallout 4?

Solution 1:

Your music player and movie player have their own control over which device to use for audio playback.

I will assume Windows 10.

On the lower right hand corner, click on your volume control:

enter image description here

Above the slider, you can see your currently active sound device.

If it isn't set to your USB headphones, change it. This should solve the problem.