Windows now not working

Hey guys, got a quick question for ya. The other day at work one of my guys was installing a sound system(amp, deck, sub, speakers, the whole deal). After it was finished the customer left to go home. He then came back the next day with this story: "i went home and parked my car, when i went to leave my house later that night i rolled up my windows. THe next day i went to jump in my car and my windows including my sunfroof didn't work now. When he tried the windows there was a clicking noise under the dash. Not sure waht could have caused it or where the problem is exactly. Any help?

what year and what vehicle is it, take it, it has a control moduel for windows and sunroof from where you said there was a clicking, what i would do is try the fuse box because it could have a seperate supply as well as the supply going to the control box, and also trace all wiring and check for condition.