Code stopped working during test until reprogrammed?

Hey all,

For the second time in my career as a tech/junior engineer, I had a board today that randomly failed mid test. Checking multiple times and it was as if all the code just stopped. This particular example was audio related and the sound went all garbled for a few seconds then vanished. The microcontroller in this example is related to the audio.

We reprogrammed it and the code took and all of a sudden everythings working fine.

Anybody have any plausible explanation? The weird...

Code stopped working during test until reprogrammed?