Has anyone had a similar experience or know what the problem could be? I searched this site but didn't find anything.

I was working on a piece yesterday and my Whip quit on me with no warning, nothing. It was all there and all fine then nothing. I changed the clip cord, then the foot switch, then checked all the contacts, changed outlets, fiddled, looked, wiggled...nothing.
I got it to run fine without a needle bar, but as soon as I dressed it again it wouldn't budge.
It was an extremely awkward moment in my shop. My customer started fidgeting and clearing her throat. I know that I should have at least three of them but I just switched from coils a couple months ago. I haven't been able to decide what to get next.
Anyway, I was about to grab my gen 6 to finish even though it wasn't what I wanted to use, and suddenly the Whip was working again.
I use a CX-2 instead of a dual power supply, but I've heard a lot of folks say that the Whip is fine with CX-2.
Is there some numb-nuts thing I'm just not getting? I couldn't figure it out. I hate having technical difficulties in front of customers, and I'm praying that it doesn't happen again.