I had the same problem with my Warwick Corvette. Not too bad for the odd little bit but for when we needed a slap line in a bass-dominated tune (can't stop by the chilis etc.) it was unworkable. I solved it easily by using the eq switch on my old Hartke VXL pedal which boosted the signal. Since selling that i've bought a clean boost (from this site) which is even better, plus i can use it for other stuff where the bass needs to be more prominent.
Your first port of call should be having quiet word with the sound guy, a bass light mix is just not on!
EDIT: Just a thought, i remember my corvette had a very low output for an active bass, was the standard 2 band MEC circuit. Didn't have the same problem with a MM SUB bass i used when my warwick was in the shop. Might be typical of the circuit?