John McCarthy answered - Well, yes, there is something you can do. We just finished a new program with Rob Arnold of the band Chimaira and we had an entire section of his program talking about this problem.
There is a pedal or rack device called a noise suppressor or noise gate that cuts off the sound of your guitar when you stop playing to eliminate this problem.
Rob uses the ISP Decimator pedal and it worked great but there are other companies that make these devices that you should check out that will also do the trick.
I wouldn’t want you to have to play an hour and a half song each show.