Symptom

Headset not working properly: speaker and/or microphone not working

Device

This is related to the USB-C Sennheiser headsets.

For example: 

The picture below shows the difference between USB-A (left picture) versus USB-C (right picture) connectors.

Solution

Check first if the headset is connected to the USB-C port of your laptop.  Most recent models of the Lenovo’s have 2 USB-C ports:

Although it should not matter in theory in which port the headset is connected, it might in some cases be worthwile to plug it in another port.

If you only have one port, you can unplug the power, or use an adapter or mini-dockingstation.

If you don’t have this item yet, you can contact your local IT Support by sending a request to help.desk@kemin.com

It is also possible it is related to the connection on the cable of the headset.  This type of headset has 2 cables: a fixed cable with a 3.5mm jack, and an extension cable with the USB-C connector.  It can be possible that this connection is not closing well.   So unplug the 3,5mm jack from the connection point (where also the volume is), and push it back in to the very end (you might need to push hard)