Ok, so the thing is that we share a rehearsal place with 4 band. The guy that is responsible for the whole room and managing things know all 4 bands and its members (plays in 2 of the bands actually). Unfortunately one of the amp has broken magically. Magically means it was functional when its owner left it and next time he turned on it was not working. Questions were asked and it turned out that a guy from one of the bands brings some random shady people that use our gear (yeah, I know...) and he kinda admitted that they are responsible for the damage. We are working on the solution to sort this out, but in the meantime how can I prevent anybody to use my bass cab (it has only one input jack) ? I need a quick and efficient solution without taking the cab home every damn time. BTW I never leave my amp (PF350) at the place since I use it at home each day. Thanks!