Enable Gestures then you can use Click (and hold mouse button) and move slightly right to skip 10 seconds, click (hold) and left to skip backwards 10 seconds.
The 10 second skip CAN be altered in the Hotkey Settings > Short Jump Length > enter required skip length.
(how to enable Gestures - https://www.vlchelp.com/how-to-use-mouse-gestures/ )
You're all welcome :)
My mistake, I was searching for a fix for the crappy 'new' video scan with mousewheel so must of got confused.
As to OPs issue, no real idea but after a quick search, I can't find anyone else that is having this issue.
Only thing I can think is that with newer versions (3.0.1) then on the Configure Hotkeys menu, there is a pair of options, one to define both horizontal and vertical axis of VLC (vertical / volume and horizontal / seek) for mousewheel, unlike the version shown only seems to have 1 axis option (at the bottom of the screenshot).
As an interim 'fix', Gestures can be used, while not as convenient as mousewheel, it should work.
Click + Up / Down = Volume Up / Down in 5% increments.