...nor do you indicate what type of headphones you are using.
The first thing that comes to mind though is to check to see if there is an updated sound driver for your sound card. Check the computer manufacturer or the sound card manufacturer's website and download/install the latest sound driver for your machine. There also may be an updated chipset drivers that will help.
Another thought, if you're using a front output for your headphones, try the rear jack.
And if all else fails, we get an inexpensive USB sound dongle and use that.
Hope this helps.
Grif
I am running Windows 10. I listen to a lot of things using headphones, but I don't get much volume, including using VLC Media Player or the Internet. The volume is set at 100%. The volume doesn't even compare to my phone when listening to the Internet.
Burt

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