Ok, so I have a practically brand new Jen Shinn 329 chassis in my UMK3 cab. Turned it on today to discover no RED being displayed. I removed the chassis and installed it on another tube and the problem remains. I have had no issues with this chassis prior to today. It is not cab wiring or anything like that. I am an amateur troubleshooter and need sage advise from the masters. Any help would be appreciated. Many thanks...