Shapshots stopped working

Sometime between now and 1st November (ish) snapshots have stopped working on my system. Any snapshot generated is 0 bytes long.

If I use the ‘Download Shapshot’ button on a standard camera card I get a .jpg file which actually just contains the text : 500: Internal Server Error

All my cameras come from a MotionEye instance and are all MJPEG.

Any idea what Home Assistant ‘Upgrade’ may have caused this, as its been working fine for years…