Logic Pro screen freeze in play mode

Hello everyone.

Recently bought a M1 Macbook Air specifically so as to upgrade to Logic 10.6.1

Having installed I find that the playhead moves for a couple of seconds and then stops, even though Logic continues play the sequence and ouput audio.

Closer inspection reveals that meters also freeze at the same moment.

Clicking almost anywhere on Logic unfreezes the display momentarily, but it locks up again a few seconds later.

I've updated OS, to 11.2.3; and followed all the suggestions on the support page - including binning and then reinstalling Logic.

I'd be very grateful if anyone could give me some kind of lead to follow here.

Thanks in advance