Hi,
I’m sorry to hear about your trouble with your new Sennheiser Accentum headphones. It sounds frustrating, especially since they work well with your phone. Windows often defaults to a lower-quality profile when a microphone is in use. Make sure your headphones are set to the stereo profile-
- Right-click the speaker icon in the taskbar and select Sounds.
- Go to the Playback tab, find your headphones, and ensure they are set to Stereo instead of Hands-Free.
Sometimes, disabling the hands-free telephony feature can help-
- Go to Control Panel > Hardware and Sound > Devices and Printers.
- Right-click your headphones and select Properties.
- Go to the Services tab and uncheck Hands-free Telephony.
Also, please make sure your Bluetooth drivers are up to date. You can do this through the Device Manager-
- Press
Win + Xand select Device Manager. - Expand the Bluetooth section, right-click your Bluetooth adapter, and select Update driver.
I hope this will help. Please let me know if you have any other queries.
Have a good day