Guitarists often connect their instrument to their amp(s) through a tuner pedal or an A-B device (to switch their guitar between two amps). Either could be used to momentarily interrupt the audio signal from your player to your amp.
Examples only:
http://www.guitarcenter.com/Behringe...Pedal-Tuner.gc
https://jet.com/product/Boss-Ab-2-2-...4e2c5c02457062
More:
http://www.thegearpage.net/board/ind...e-pedal.93729/
:))BOB