Connecting clips timeline bug?

Is anyone else getting strange timeline behaviour? From a new project connect, overwrite, insert or append work as advertised, however once my TL gets involved with lots of compound clips, attached storylines and effects at some point adding clips to the TL via KB shortcuts, menus or on screen buttons makes the TL jump about 10:00:00:00 to a null area with no gap - a part of the TL that doesn't exist. I then have to zoom to fit to get my TL back on screen and manual zoom in and scroll to the skimmer.
It's driving me mad!
Any solutions?

Seems that working from duplicated projects might have been the issue. So I tried cutting and pasting into a new project . If I select all and cut and paste the clips the bug persists. But by copying and pasting sections at a time into a new project I now have a full sequence and adding clips works correctly🤷🏻‍♂️.

I remember reading about this bug a couple of versions back. What version of FCP are you running?

Sadly bang up to date.

Seems FCPX has been accumulating bugs and Apple's not keeping on top of it.