Hi Daniel_BBB,
Greetings! Thank you for posting in Microsoft Community.
I'm sorry to hear that the Surface App doesn't work properly. Just to confirm few questions:
- May I confirm the host device that you're using to download and connect the Surface USB link?
- Is this the Surface app (Get Surface - Microsoft Store)) or the Surface Audio app (Get Surface Audio - Microsoft Store))?
Please also perform the methods below:
- Run the Surface Diagnostic Toolkit.
- Check if the Surface app has updates in Microsoft Store. Click the three-dots option on the upper-right corner > look for Surface app then update if there are needed updates.
- Uninstall and re-install the Surface App. Go to Settings > click on Apps > Look for the Surface App then click the Surface app > click Uninstall > Re-install the Surface app.
- If the issue still persists, try to uninstall back the Surface App and install the Surface Management Extension instead.
You've also mentioned that the Surface USB link is broken or damaged. After you plugged in the USB link, try to press and release the power button quickly to turn on your headphones.
Do you hear a message saying they're connected to Microsoft Surface USB Link? Do you also see an solid white LED light on both your Surface USB Link?
If your Headphones doesn't detect the USB link then you need a replacement USB link.