Just in case it helps anyone, I've resolved this problem by downgrading to Ubuntu 19.04. Deluge won't run on 19.10 on a Pi.

I'm trying to run headerless Deluge on a Raspberry Pi 3 running a fresh install of 64bit Ubuntu 19.10. When I start deluged it crashes and even on debug, no errors are written to deluge's log file but this is written to /var/log/apport.log: called for pid 4954, signal 11, core limit 0, dump mode 1 s...