to reset the pram start up the computer and hold down command+option+p+r and let it chime 3 times
Douse it happen when you plug it any anywhere or only at your current location – the reason I ask this is because it didn’t happen at the place you took it to.
If it happens other places then create a new user and see if it happens from there, if it douse then it is ether the OS or the hardware.
To eliminate the OS reinstall it.
if if continues to happen then take it in, and like I said I have always found the the geniuses at the Apple Stores know much more then, people at places not owned by Apple.