Audio Disappearing Issues with Premiere Pro

I am running the latest update of Premiere Pro on a MacBook OSx High Sierra and I am seeing a few posts on this but no answers other than maybe downgrading versions.  I am assuming that my project that was updated when i opened it will be able to be saved in an older version but i wondered if there was anyone who has found out the answer yet.

The issue is that random audio keeps disappearing - it can be one clip thats in the timeline and has always had audio, when you open the project its flat-lined, nothing there.  Sometimes it comes back when you close and re-open but not always and even if it does, when you export the media for your finished project that bit of audio is not there.  Very frustrating, taking hours of my time. 

Have done the usual reset preferences, delete media caches, delete premiere and reinstall.    Have even moved the project onto a PC with a new install of premiere and its the same there.  It seems to be happening at the same time as InDesign is also having problems - are they related?

Any ideas?

Martin