AI, which isn't always 100% accurate, offers this...
"When the Controller Wizard in Express Scribe recognizes button presses (showing "YES"), but the buttons don't work during transcription, it usually indicates a configuration or driver issue, or a mismatch between the wizard's test mode and the active controller mapping during live use.
Troubleshooting Steps
Make sure the controller is properly set as the "Active Controller" in the Express Scribe settings after running the wizard. If the device is unplugged and replugged into a different port, rerun the wizard and reselect it as the active controller.
Double-check that "Enable foot pedal controller" is checked in the Control settings.
Reset command mappings to default in the Control panel’s "Command map/test" section—sometimes custom mappings interfere with live operation.
Verify the correct drivers are installed, especially for VEC/VPE and gameport models. If drivers were missing or installed anew, restart Express Scribe after driver installation and check the port selection in settings.
If the issue started after switching editions (e.g., upgrading to Pro), contact NCH support or check the support forums, as licensing issues or bugs have occasionally caused this type of problem for newer Pro users.
Additional Checks
Only use pedals compatible with Express Scribe's listed controllers, as some proprietary pedals are not supported.
Confirm that no other programs are capturing controller input, which could block Express Scribe from receiving commands."
If these steps do not resolve the issue, contact NCH technical support for further assistance