Stuck key (and is that a diagnostic LED display)?

I’ve had my Quiet Click keyboard for a while now, and have been using it quite heavily, although I haven’t yet started to modify the firmware. Now the backspace key has started to have problems: at first, it started repeating on a normal short keystroke (as if not released), and now it is not working at all.
If I cycle through the LED patterns with the LED key, in the step after the “all off” step, it lights up just that key, with red; is this an indication that the key is stuck “on”? And is the solution to replace the key?
The key action feels normal to me.
Thanks for any help!

I’ve had similar problems, when I first got my Model 01 and later with some of the keys. My problems were solved by removing the key cap and cleaning them with alcohol. I believe there is even a section in the FAQ on how to do this.

I would suggest cleaning the switches first and if that doesn’t solve it try contacting support.