Sporatic Monitor Issue

I have a friend experiencing a strange and annoying problem regarding their monitor. Recently, after no problem for 2 years, their monitor sporadically displays the 'contrast setting adjustment window.' In other words, it's the window that would normally only appear if you were physically pushing the buttons on the monitor to adjust the contrast.

They can close it by pushing one of the buttons on the monitor, but it keeps reappearing. It's verry frustrating. Otherwise, the computer functions normally.

Any suggestions would be appreciated.

Thanks