Jupiter 50 USB Memory Problem

[Voxneon]

My JP50 has developed a problem whereby it wont read or write to any USB sticks.
I have tried several but none will work even after re-formatting.
The problem occurred after I had loaded a new Arpeggio MIDI file on the USB stick and loaded it into the JP50.
There was a read error message but the new arpeggio had loaded and was playing fine.
I switch the synth off when I had finished but when I switched it on again all of my user arpeggio styles had gone.
I have tried re-loading them but I get the same error message even though they appear to load and play ok.
I have also noticed that I cannot backup to any USB sticks either as I get a write error.
It starts off fine but then throws up an error when it gets to 8%
I have no idea where to turn next as there appears to be an issue with the USB reader.
I'm not sure if its the socket or something internal.
Has anyone experienced anything similar or does anyone have any tips