This is the newest OS version 2.49 for the Ensoniq EPS.

As costs have skyrocketed so have new blank 1 hole disks which cost $4.30 each these days.  In the interest of saving our customers money we have started using new 2 hole disks and covering the 2nd hole with scotch tape.  They work great, just like a 1 hole disk.  If the tape starts getting wear from use, just replace with another piece of scotch tape.