Thanks for the replies, much appreciated!
Hamid, yeah, I have render preview disabled.
Steve, I’ve been looking at the Activity Monitor, and I can see the aeselflink processes running that AE starts up for each cpu. The percentage of cpu that they consume spikes every time that the render process moves on to the next item in the queue, and does that thing where it sits and thinks before rendering the frames. Sometimes it manages to move on to the next comp in the queue just fine. But when it doesn’t, this is exactly where it crashes. It creates the next file but fails to render any frames, leaving an incomplete .mov file of 0kb.
It just did it again, and I looked at the activity monitor while AE span uselessly in the background. Nothing seemed to look really strange, except that After Effects was now in red. But I don’t claim to really understand the activity monitor fully. I put some screenshots online, in case anyone has time to take a look and give me any feedback.
https://www.edpurver.com/ae_1.png
https://www.edpurver.com/ae_2.png
https://www.edpurver.com/ae_3.png
I really need to get this fixed, because overnight renders just stop and hang after a few comps and I’m losing hours of precious rendering time.