I use a Sony TX650 device for recording audio notes. It allows me to increase/decrease the playback speed and helps me in faster transcription. However, it is not always efficient because when doing a transcription on a machine, I need to juggle between the player’s controls as well as the keyboard.
Transcribe Audio or Video Offline
To alleviate that, I created an offline transcription software. It is a single page HTML file and using Javascript and HTML5 Local Storage you can do transcription of both your audio and video files – and export the content.
A demo is available at
https://exain.com/transcribe
and the source code is available on GitHub at
https://github.com/technotablet/transcribe
Vivek's blog 
Very nice point, but I would also add that I am using a service that is transcribing speech to text (https://audext.com/speech-to-text/). It is fast and helpful.