Logic Pro X Impossible to cut Audio regions when one track is 'armed'


Never encountered this before.
Maybe I have to reset a preference/setting??

If I arm an Audio track - ie click the record button on a track it makes cutting any audio region impossible when the song is playing - either with scissors or cut by locators etc.
Deeply frustrating as I often audio on the fly, sometimes even while recording another piece of audio on another track.
The editing functions work again when I stop playing the song.

Another problem involving cutting audio files has reared it's ugly head when attempting to cut an Audio Take Folder.
If I cycle around a chorus, record a few BV takes - swipe to comp my fave parts and then decide the second half works best, when I attempt to cut the take, large parts of the wave form suddenly disappear from the take folder!
If I undo they come back, but I have never seen Logic behave like this before. So is this some behaviour based on a new feature meaning audio take folder work differently since LPX?