Now that I have my separate audio and video files for the first interview, I began the task of syncing all the footage up. For previous projects I have gone about this manually, using a clapper board to create an audio peak as well as a simultaneous visual cue. This method is extremely time consuming when anything more than a single 5 minute interview is concerned.
To try and speed things up I got myself a trial of a program called PluralEyes. This software is capable of taking multiple camera angles and audio sources and syncing them up automatically using the camera captured audio as a reference. The first step was to import all the clips into the software.
Once all the clips are imported all that needs to be done to line them up is hit the synchronise button and PluralEyes handles the rest. An xml sequence then needs to be exported from the program and then imported into Premiere Pro. This creates a sequence with both audio tracks intact, and one with only the audio from the dedicated recorder intact.
This method has already saved me considerable time and will be how I do any syncing of audio and video in future.