Thanks for the offer Rob, as it's not my kit i'll have to let it's new owner decide which batteries he's gonna use, if he still wants to use my NiMh's we'll give them a go on the current esc settings & see whether it keeps cutting, maybe then i'll take up your kind offer.
Interestingly even the basic card you have i can't seem to find for sale on it's own anywhere, does seem strange to actually include a list of different esc settings but no card or even a clue as to how to adjust them
Cheers again