Hehe...turns out that after I cleaned all the motors up, fitted new brushes and all that....the problem turned out to be something much simpler.
The steering post was slipping and when I looked deeper into the problem I found that it was actually glued on and the teeth are all mangled underneath!
Anyway, I glued it back on again for now...this seems to be the only way forward until I can get some spares...and everything is all good!
Let this be a lesson - even if it doesn't look loose - check it anyway!
