Volume ~ make it stop !

HELP.....

I've reset my PMU as I was having problems with getting a black screen on start up. OK that's now resolved BUT

My Volume keys don't appear to work any more. Mute does mute and un-mute. Min doesn't appear to reduce the volume to mute, and increase vol does JUST that. TO MAX ! I then can't reduce it via the vol. reduce key. Have to mute and the goto system preferences and reset volume to a reasonable level.

Why have the - and + vol keys got messed around, and any ideas how I fix it ?

Cheers

Resolved following reboot with Pro speakers plugged in. Was first power on following PMU reset. For some reason it maxed out the vol when tapping the vol increase....

Paniced and couldn't find the sound section in Sys Prefs fast enough !

All fixed now