Hi David,
Let’s follow these methods and check if it helps.
Method 1:
a. Press Windows Key +X, select Control Panel.
b. Select the "Sound" menu.
c. On the Playback tab, select the Bluetooth headphones, click Configure, and then make sure the configurations are set correctly.
d. Check if your Bluetooth headphones are already set as the default device.
e. Select the sound device that you want as the default sound device, and then click Set Default.
f. Click OK to save your settings and to close the Sound dialog box.
Method 2: Uninstall and reinstall Bluetooth drivers.
I would suggest you to uninstall and reinstall the Bluetooth****drivers from the manufacturer’s website and check if it helps.
Do let us know about the results. We will be happy to assist you further.