If you purchase the digital recorder, you will get the playback software along with it. Olympus ships its proprietary software to download the voice files from the player into your system and also works as a player to listen and transcribe.  You can use Express Scribe, a widely used audio player for transcription. It is a freeware. You can use to playback the files forward and backward using either function keys from keyboard or a foot pedal.

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