Rockola 1493(Princess)

Hi
I have a selection problem with this machine, the selection of records works partially for example A5, A6, A7, A8, A9, A0 and A3 will all select properly, but A1,A2 and A4 will result every time in the selection lever for A0 being moved into the play position. This happens also when you go down through the various letter and number combinations, anyone any ideas
regards
seancalla