Express 24/48 console Flickering Light Problem on one Unison rack

Our church has an Express 24/48 console (EXPRSS 24-48 Model# 110A1005 S/N: EXPS-7936 12-22-00) connected to two Unison racks (24 slots with 24 modules on left rack and 24 slots with 6 modules on the right rack). There is also a touch screen with 5 presets and another 5 push button preset panel. As soon as the power switch on the Express 24/48 console is turned on, regardless of presets, the lights in the left Unison rack start to flicker. The green LEDs on those modules in the left Unison rack also flicker. The lights in the right Unison rack do not flicker, nor do the LEDs on the right Unison rack modules. If the Express 24/48 console is powered off, the flickering stops, and all lights work properly with the presets. We have already swapped the modules, blown off any dust, cleaned filters, and done a hard reset by turning off the circuit breaker for both the Unison racks and the Express 24/48 console. This has not changed/resolved anything. Still the same exact lights blinking as soon as the Express 24/48 console power is turned on. Is there any diagnostics or tests I can perform to help isolate what is failing? I am an Electrical Engineer, not a theater person, so I may not be using the correct terms. Just trying to help. Any help appreciated. Thanks, M Yamrick