speedo fault

Hi, the speedo on my gti is all over the place.  When I get to 30 mph its ok, after that it starts to go all over the place.  When im doing 50, the needle moves from 50 to 80 mph and you cant tell what correct speed your doing, the clocks also start to make a rattle noice that gets louder as you go faster.  Is it the cable, or the clocks, I hope its not the clocks as its got the correct milage for the car and I dont want to lose that.

Any ideas??

thanks, Joe

I would guess the cable but not certain. You could take your radio out to reach behind the clocks to double check the cable is clipped on properly.

My money is on the clocks , common problem sorry .