Hi, Selene Orozco!
Thanks for reaching out to Microsoft Community. We are sorry to learn you have issues with the microphone not working on your Surface Headphones 2 when connected to your Surface Book. Thanks for taking the time to let us know about this and allowing us to help you out.
To troubleshoot the issue, please check the following steps:
- Check to see that Surface Headphones Hands-Free audio profile is set as the default Windows sound profile on your Surface Book.
- Go to Settings > System > Sounds.
- Under Choose your input device make sure that **Headset (Surface Headphones Hands-Free)**is selected.
- Check the Windows application settings to see that the Surface Headphones Hands-Free audio profile is set.
- Go to Settings > System > Sounds.
- Under Other sound options, select App volume and device preferences.
- In the list of apps, find the application that you’re using.
- Make sure that the Input for that app is set to Default, because the master input setting was set to **Headset (Surface Headphones Hands-Free)**in the previous step.
For further steps, please visit https://support.microsoft.com/help/4491959 to be guided on how to troubleshoot your Surface Headphones 2.
If this answers your question, please let our Community know by marking this post as an answer. Otherwise, don't hesitate to respond to this thread if there’s anything else that needs to be addressed.
Kind regards,
Janette_Z