Tonight, while sending absolutely no signal to any input on my Quantum 2626, and not even doing anything music-related on my computer, all eight front panel input LEDs spontaneously went from extinguished to steady red for about 5 seconds, and then went back out again. I swear, there was no signal of any kind being sent to this unit, and I heard absolutely nothing through my monitors during the event. What could this have been? I am concerned that this is some sort of hardware fault indicator that I don't know about. I'm on an iMac running Mojave 10.14.6. Firmware is up to date at 1.3-82.