I did try a few cables but this morning i tried one from a portable hdd that was only about 30cm long and it works fine.
It looks like my s10 and the 1m long cables dont work well with it.
Cable is common.
I've found connecting to an aftermarket unit that the long aftermarket lead keeps dropping out, no stability etc.
Swapped back to the original cable (although loose usb port) and it works much better.