Multicam - clicks at edits

I've recently finished a short multicam edit with2 video angles and a audio track loaded as a third angle.

All synced fine and the edit was done with only the video angles switching.

The edits look fine in the timeline - grey dashed lines for the video and white for the audio. My understanding of this is that the audio would be uncut at each edit - not merely a through edit.

As part of the audio workflow, I exported the audio only and reimported it as it is easier to work on.

At this stage, I notice that here is a very slight but audible click (more accurately, an anomaly) on each cut - it even shows in the bounced audio track waveform as a moment of silence perhaps 2 frames in duration. See screenshot below:

I can recreate it in the same project but not in a new library with totally different material.

The only thing that looks strange is the video source has 44.1kHz audio (iPhone camera), where the audio only track and the project is 48kHz. Is that likely to be the cause?

As I finished typing this, it occurs to me that it might just be the audio rate mismatch and I may have solved my own puzzle. But I'll leave this here in case someone recognises it as something else or it provides useful to others.