Audio Echo from Screen Recording - How to remove single audio stream

Hi All,

I used my iPad to capture a screen recording of a live stream - unfortunately, I had the "Microphone On" setting switched on when recording and so the audio of my video has a really pronounced echo, I'm assuming this has happened because it the video stream has its own audio and the microphone input is now overlaid on top of it?

Does anyone know of a good way to separate out one of the audio channels to remove it? I loaded the video into iMovie to try to play around with the equaliser/reducing background noise but it had limited impact on reducing the echo (and I couldn't find a way to separate out the audio stream into individual channels).

As it saves as a single video file - will the audio streams actually be separable?

All suggestions welcome - the screen recording saved as an MP4 format.

Thanks,

Richard