drag and drop not working, MacBook iTunes to Clip 2gb

I’ve had a 2gb clip for a few months and had no problems using it at all, transferring music to and from it without issue. then out of nowhere its not accepting files when i drag them from itunes on my macbook. it seems to acknowledge the files initially, the little box saying “preparing to copy x-amount of files” comes up, the files begin copying (in the music folder of the Clip the ‘white sheet’ file symbols that you get before the mpeg file symbol when the file transfer is complete, start appearing) but then the files start disappearing to zero and the copy hasn’t worked. if i try the odd few songs or one album, it will sometimes work but sometimes not, if its over fifty files it never works.

i’ve tried searching the forum for a solution but cant seem to find quite the same issue.

any suggestions most welcome.