I've gotten the same issue. I press Ctrl-M, set focus to vlc player, press space bar and then it toggled pause by itself. Here is the log (verbosity 2):
main debug: auto hiding mouse cursor
main debug: toggling resume
main debug: toggling resume
mmdevice debug: state changed: 0
Then it pauses, it then continues and the following shows up:
main debug: toggling pause
main debug: toggling pause
mmdevice debug: state changed: 1
main debug: auto hiding mouse cursor
This will continue even if I close VLC and restart it. Thought it was a keyboard issue, but I'm not getting any issues with any other application. This has happened on my other Windows machine too. That one running Windows 8.1, this one running Windows 10. Both are convertible laptops, though I don't think that it is the reason since this was reported over 10 years ago.
If there is any other information I can pass on, let me know.