This is similiar to the external CD writer Apple sells which ONLY works plugged into the Mac USB itself. It would and will not work from an external USB Hub, even a powered USB external hub, nor will it work from a splitter off my Mac Pro USB port. The problem turned out to be that my foot controller had to be plugged into my Mac Pro USB port itself. I can now recommend this application after developer assisted * Automatically sends typing to those who dictated the workĮxpress Scribe Pro for Mac OS X is the perfect software for helping professionals improve their transcription productivity. * Automatically receives and loads files by internet (FTP), email or over a local computer network * Dock both analog and digital portable voice recorders to load recordings * Uses 'hotkeys' to control playback when transcribing into other software (e.g., Word) * Supports professional USB foot pedals to control playback. * Plays most formats including encrypted dictation files. * Variable speed playback (constant pitch) This transcripton software also includes important features for typists including variable speed playback, multi-channel control, playing video, file management, and much more. Install Express Scribe for OS X and control audio playback using a transcription foot pedal or keyboard with 'hot keys'. Express Scribe Pro Transcription Software is a professional audio player software for Mac OS X designed to assist with the transcription of audio recordings.