Graphic LCD screen displays garbage randomly

Any ideas what could be causing this ? ( image attached )

Graphic LCD on Ramps & Mega 2560 with Marlin.

The SD card that is part of the LCD unit is still working as the print is still running.

Happens every few weeks. Sometimes hours in to a print, sometimes within minutes. No set pattern for timing.

Have changed cable from LCD to Ramps to metal shielded cable.

Is there a Marlin routine or function that I can call with a button press to a specific pin number that will reinitialize the LCD display, without affecting the SD card operation ?

Some LCD's are very sensitive to static electricity. Check that your frame mount is connected to earth and also that your LCD is properly isolated. Sometimes the SD port charges up because of the plastic of the SD.
We have some Rostock's at work and from time to time the LCD's behave just like yours. We reset the machine and everything comes back to normal. We re-oriented the cabling behind the LCD Controller and we have not gotten the problem sinces a year

Thanks for the advice.

I stripped the LCD unit out of the printer and checked everything thoroughly.

There is a small L-shaped PCB that connects the 2 cables to the Ramps board.

I found a small 'splash' droplet of solder right between the MISO and MOSI pins which I guess must have eventually made contact and scrambled the data going to the LCD.

Cleaned the PCB and been printing for 2 days without any issues again.