Shift key problems

[Xenial]

Hi
I have a Sony Vaio VGN-FZS1S and just the other day the shift keys have started to play up. Sometimes they work and sometimes they don't. So I could type a sentence holding the key and some would be in capitals and others not.
Anyone got any clues?
Thanks

 

[Xenial]

does it happen with both left and right shift keys? what about in dos mode safe mode etc.

ps nice typo i would edit it

LOL re the typo!

It happens with both shift keys. Running Vista Home Premium - not sure how to get it in safe mode.