If you are having trouble getting your Real Tone Cable to register correctly, there are a few workarounds you can try:

1. Open up your Device Manager
2. Expand the Sound, video and game controllers tab
3. Locate Rocksmith USB Guitar Adapter, right-click on it, and select Uninstall
4. After Uninstall is complete, unplug the Real Tone Cable
5. Plug the Real Tone Cable back into your USB port and let it automatically install the new drivers
6. Launch the game and enjoy! 
 

If still experiencing issues, Windows 10 has privacy settings for certain devices. This means that by default, microphone access for applications is blocked.

To adjust the privacy settings for your microphone, please follow these steps:

- Open Windows Settings by right-clicking the Windows logo located on your taskbar and select Settings.
- In the Settings menu, click on Privacy.
- Select on Microphone from the list on the left.
- Ensure the Let apps use my microphone option is set to On.

This should fix the issue.