Unit hangs

[ebolisa]

Hi, I've been running this hat for quite some time as an alarm clock display connected to a Rpi 0 2. The latter is also connected to a sound card (used to play music in place of a standard alarm buzzer) but using, obviously, different pins.

I noticed the display randomly (every 2/3 weeks) hangs so, I thought it was the Pi board doing as I experienced this failure with similar Pi0 cards in the past. However, because I can SSH in and execute a reboot, I'm convinced the display hat is hanging (not refreshing). I already eliminated a possible temperature or PS issue. Because there's no feedback from the board (at least I don't know that), I cannot catch it in my code to issue a possible reset.

Having said that, what could cause it? Could it be the onboard chip? TIA