Deep Architecture error message, Logic Pro X

Having spoken to an Apple engineer today, it seems this error message is synonymous with older versions of Logic. That didn't get me a solution though... when tracking audio, particularly when editing and comping Take Folders I'm repeatedly getting 'Deep Architecture! Please unpack some folders!'

This is not restricted to one project and is blocking workflow at a deeply frustrating rate. I have plenty of CPU and the projects are really not that heavy on content or plug-ins.

Done all the usual stuff: restarting, resetting preferences, etc. .. when it does (eventually, after several restarts) let me delete takes, the solution is temporary.

OS Sierra, Logic Pro v.10.4

Any ideas? Is this really unknown in LPX..?