In the interest of sharing knowledge, I think I have solved the issue.
I finally got around to swapping out a working speedo cluster into my gfs car and all is fine. Tried the non-working one in another car and it shows the same symptoms, thus clearly pointing to a fault in the cluster.
On a different note I would highly recommend driving around without a speedo or working fuel gauge, keeps you on your toes lol (don't worry I was using GPS for speed most of the time)
Thanks for all of your time.