Hi I assume you've removed them from the covers and run them bare. Also try cleaning the pulley surfaces on the drives. Even tiny grunk here will cause read errors. The belts tend to degrade and make blobs on the pulleys. Clean heads between each experiment. I had this same problem with a number of "high quality" floppies. It seems that the adhesive used for the liners would seep through the liners onto the disk. Someone mentioned using goof-off but I've never tried such and don't recommend it without some testing first. I cleaned with isoproponal(sp?). Dwight