Hrm saw some more responses on the forum.

Serial #: 21X3L1S5739017695 bought and registered in December of 2007, seems to be before the 5749 improved footswitch design.

The other post was yesterday, seems like these foot switches are only lasting around a year?

Bothersome that I have a gig in a few days. Going to rush to a repair center....

Can anyone confirm the serial number thing?

"Another victim of bad switches,like myself.10 min.ago i answered to similar thread,so here goes copy paste:

There is a test for the buttons, hold the right arrow key while powering the unit on, use the down arrow select the Buttons and press the Inputs button, now as you press the buttons the 00 will change to 10 when you press the button down and then to 11 when you let it go, go through all the buttons to finish the test, this will quickly tell you if the problem is a hardware failure. If it is, you'll have to get it to a service center. If the X3L is new you might see if you can exchange it for a new replacement where you purchased it. If it is a switch failure you should be aware that there was a change in production to improve the switch design, you can tell by the serial number if you got the old or new design, here's the info on that: Serial numbers starting at 5749, i.e. (21) X3L1S 5749 XXXXXX, are the updated ones. I don’t know if this info has been confirmed but it seems to be accurate. Oh, and don't open it up, you'll void the warranty, and the switches are warranted for life for this kind of failure."