HVAC display flickering

The HVAC display has started flickering on and off. Sometimes completely off, but a smack on the dash pad above it will bring back the display. All functions working properly otherwise though.

I'm guessing it's probably a cold solder joint on a circuit board, but before I tore things down I thought I would ask: Has anybody had this problem before? What was your cure?

It is either a cold solder joint, or a bad ground (that could be a cold solder joint).