Alright-figured it out. Something is wrong with the steam archive.
There's some kind of corruption with the package that's uploaded there because I've cleanly reinstalled many times but when I verified the installed files-it found like 70 that needed to be replaced. Now it's working.
So a dev probably needs to reupload a clean version. This kind of coincides with another bug report I read where the guy was having popping issues with a .wav file. I think something got corrupted.
Good to hear it got solved, although the actual cause of the issue may remain (likely a system dependant?) mystery.
Verifying integrity on Steam only compares if the files on player's hard disk are exactly same as the actual game files on Steam servers, and if the player's files
are different it downloads the original files from the server again. So, if there's been integrity failures it has happened to the files either during or after the game download (ie. installation). And vice versa, should the game files on Steam servers be corrupt/malfunctional the integrity verification then verifies that they are just as corrupt on player's hard disk too.
