Question Weird monitor clicking noises

[Aggressive Combo]

So i have 2 monitors and my old monitor does weird things 1) when i get a game in full screen on my newer monitor sometimes my older one flashes and after that says "no input" and after that it says "input not supported" and then it shows static like on old tv's BUT it is like a 2018 monitor do i dont know how that is possible and when it is in static i HEAR extremely loud clicking noises in rapid session. If you search up weak signal tv on youtube you will see what i mean.

 

[helpstar]

which monitor brand and model s it?

which GPU are you using?

How are the monitors connected to the GPU?
check the cable connection, is it completely plugged in?