Deliberately ran my transmitter dry at Saturday's gig. I'd had a single bar on the r/h side of the display for a couple of hours, and I wanted to know what happened when the batteries finally died.
I could have done this at a rehearsal, of course, but where's the fun in that?
Penultimate song of the second set (the Admiral Nelson in Whitton is a 3-setter finishing at midnight) and I was singing the second verse of Jumping Jack Flash when the sound of my bass started farting and cutting out. I kept going for a few bars in case it came back (temporarily) but it simply got worse.
I'd already laid out a cable beforehand, ready for when it happened, so I dropped out for two bars - still singing - while unplugging the wireless and going cabled.
In truth, it wasn't much of a mystery that needed solving but I've had battery-powered units go dry in several different ways and I always like to know what happens.