Monitor Burn in ?

[sealslayer]

I'm using a 21" PC Monitor on my cab and have a rather strange screen that's appeared.
I was taking my CP off today and the bezel was pressing the monitors setting buttons on and off ( Screen size, degauss etc ) now the monitor wont turn itself off and flashes the words "Burn in" in all four corners then the middle of the screen.
It works perfectly when I turn the PC on, shows the boot up screen and plays mame with no problems, but when I shut down the machine it still says "Burn in" and wont power off so I Have to turn it off from the plug.
Any ideas if I've broken it somehow?
Cheers in advance 

[grantspain]

sounds like the monitor settings have changed due to the bezel,logically i would say the burn in text is an anti burn in feature in settings,just bring up your osd and have a mess around

[sealslayer]

I had a look in the OSD which oddly only appears when I boot the PC up not when its having its burn in flashing session but couldn't find anything to reset etc.
I forgot to mention that the control panel for the OSD options is loose and its soldered connections on the PCB may have touched the metal cage that holds the tube in place.

BTW just to show my stupidty what is burn in?

[SirPeale]

http://en.wikipedia.org/wiki/Phosphor_burn-in