All output LEDs glowing would be evidence of a clock loop. A clock loop can cause random patch changes, stuck notes, missing notes, etc. There are two ways to correct this. You could use the filtering capabilities of any interface supporting clockworks to filter these messages. MIDI clock is a real-time message, so you would filter out real-time messages on the inputs of the interface in clockworks, on all midi channels. You could also find the parameter that turns the clock on or off on all your keyboards and drum machines, and turn these OFF so they are not transmitting beat clock. This usually means setting something in the keyboard or drum machine to "midi" or "external" as it's clock as it's clock source instead of "internal".