Hello BrutusIn9, you may want to disconnect and reconnect the pedal to your computer, open Express Scribe, go to Options > Control, and run the Controller setup wizard, make sure you set each pedal to do the command you want. For example, the Middle pedal to be Play, the right pedal to be Fast Forward, and the left to be Rewind.
Once you have set the pedals you may Click on Finish and test the pedal.