rs23 olympus foot pedal freeze in USB

We have two models of foot pedals in our office for our transcription
programs.
1- The rs25 are working perfectly.
2- The rs23 are constantly freezing when connecting in USB.

We have connected the rs23 on different computers (Dell, HP and IBM)
but the problem remains. We have also tried to connect it on different
usb port with no result.

In the other hand, we don't have this problem with the rs25 that can
be connected in any USB port on any computer.

Is there a known problem with the Olympus rs23 foot pedal ?
.