Many laptops have an app to control this setting. It's not a driver. This has been spotted to happen with registry cleaners, malware and folk that don't use the stock OS.
Bob
I am having a very annoying issue with my Thinkpad Yoga S1. The volume bar is always up in the corner of my screen and I can't turn the volume down. Whenever I turn the volume down, it goes right back up to one hundred. I have uninstalled and reinstalled the drivers, checked for updates, but I still have this problem. Please help!

Chowhound
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