Question:  We have your clear-com PL system and the FL-7 suddenly began flashing for no apparent reason at the end of a gig. We've naturally changed all the connecting cables and it still flashes. The audio actually still works but the light keeps flashing as if it was in a channel that doesn't pass phantom. Not sure if this means our base station has just failed or what. If you have any ideas, we would be most appreciative.
Answer:  Usually the reason a Fl-1 or FL-7 flasher will start flashing on it's own is a defective 3-pin XLR cable which has a short between pin 2 (+30Vdc line) and pin 3 (audio line).  The FL-1 / FL-7 flasher works when a call signal is sent from the main station, remote station or attached beltpacks.  This is accomplished by sending a momentary 5Vdc pulse on pin 3 of the intercom line which slowly bleeds off.  If a short occurs between pins 2 and 3 of an XLR connector or somewhere internally on the intercom cable line then the 30Vdc signal is placed on pin 3 and the flasher module will flash repeatedly until the short is removed. 
Remove the sections of the intercom system until the short is discovered and replace the defective cable.