Shows how often I go in to Bigbox! Thanks, I enabled it, set LeftAlt as the hold key, then b for vol down and n for vol up. It worked for around 10 secs and then just stopped. Stickykeys are disabled, no other funky mapping programs installed or running, multiple reboots/power cycles and turning settings off/on/clearing out keyboard mappings in Bigbox etc.
This sounds like I have to fire up another thread somewhere on here for that, but ideally, if anyone could help me with the AHK above to do the same thing, that would be amazing, thanks.