Unrecognised audio by Premiere Pro

Weird Problem

I have just recorded my screen as an MP4 with an MPEG4 codec, playing the video back all works fine: the video is goo, computer audio good, computer mic good. It plays back fine in every video player but as soon as I put it in Premiere Pro CC 2015.3 it says the clip has no audio.
Similarly trying to open it in Adobe Audition it says it is a clip with no audio.
I opened the clip in PluralEyes and that played with audio but then when I export it into an FCP format for PP, opening this in premiere takes the footage offline then when re-linking says it has no audio.
Converting the files in Media Encoder has not had any success, nor has re-recording the footage with H.264 codecs. Previous versions of PP have the same problem.
I have tried lots of solutions from threads that are similar but nothing seems to be quite the same as this.

Any Ideas from anyone?

Cheers

Convert with Handbrake and also set it to constant framerate and try again.

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