Jumping Speedometer

[Sand and Gravel]

The speedometer on my 1988 Perentie jumps around while driving. At low speeds, it is all over the show but as I get up to 80 to 100km/h, it settles down and is reasonably steady. Is this likely a) normal, b) a faulty gauge, an issue somewhere else in the vehicle?

[Blknight.aus]

drive cable.

its either been damaged (kinked) and needs replacing or its gotten dry in side and wants lubing.