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 the MIDI Timepiece, or MIDI Express to filter these messages. MIDI clock is a real-time message, so you would want to set the filters to filter real-time messages on the inputs of the interface. You could also find the parameter that turns the clock on or off, and turn it off on the MIDI device that is transmitting the clock.