Haven't had a chance to get out and image for about 6 months. So the first thing I did was update all my RasPi 4 software, Pi firmware etc. and ran into a strange issue where KStars will crash every time I try a focus, or align - it seems immediately at the point where the image is received. In the CCD tab I can take a capture and the fits viewer displays the image no problem.
Have turned on the relevant logging, and disconnected everything I can except the camera itself and the issue persists.