To reinforce what Serra Ava says(and he's a lighting guy and I'm a sound guy), sound and lights should ideally never be on the same circuits. Both have very different requirements.
I would start with Serra Ava's advise, but also what are you pushing with the packs? This may reveal a current draw situation. It's not 100% true that each pack should have its own circuit or not, but that depends what you're turning on/off with it. It is a good rule to adhere to though: 1 pack/circuit.
I think something along the lines of poor utilization of house power through an improper wiring plan. Electric should be done by an electricianl, but should be done under the guidance of the lighting or sound or AV techs so it's understood what needs to be where and why.
Call support, have a screw driver handy, good work lighting and be prepared to be very descriptive. You're going to be their eyes and ears over the phone.