Ah, I remember back when I had the A500 in use. Broken CIA chips could do strange things to floppy drives. I had one that was defective, and did not know about this at first. The symphtom was that every time a new disk was inserted, the internal drive started to "chew" on the disk until it was unreadable. We thought there was somethink wrong with the disk and inserted a new one, and then that was gone as well.
Replaced the CIA 8520 chip and it was ok again.
