All of what is said above is correct. The signal chains are quite different and you need to set it up for Live. Do not fret too much as you will get it sorted. I woudl suggest trying different profiles as some sound better for certain applications and don't necessarily scale up in volume. I use my KPA in the same way i.e. for live through a PA.
Good point about the different profiles. I use completely different profiles at for recording/through my monitors than I do live. Definitely took me longer to get sorted out than a regular amp, but once I did it was a lot more consistent (other than a recent problem I started having).