CompuServe Messages

I have a very strange problem with 2, yes two Toshiba XM-330 ITA CD ROM Drives. They both give an -127 error, with two different software drivers on 4 different Macintosh Systems. Both CD ROMS are brand new, the 2nd drive was sent, because I suspected the first one to be faulty. When the error occures, the CD disc either ejects, or a clicking noise is heard. I have tried all my discs ( all 6 of them !) with the same result. Could it be the caddy ? Any suggestions would be appreciated. Thank you in advance… PJ