Hey @Charlie_Scientist, welcome to the Nextcloud community and thanks for supporting Nextcloud snap 
Sorry to hear you are having issues with your Nextcloud snap installation. If you’ve come this far, you’re on the right track! There is a good chance someone in the community has had a similar issue and knows how to resolve it. That depends on how you request assistance. So read your request for tone, avoiding hyperbole and assuming good intentions.
Below are some links to how-to’s answering frequently asked questions and may help you help yourself;
- How to install Nextcloud snap
- How to configure Nextcloud snap
- How to edit config.php for Nextcloud snap
- How to use OCC management console for Nextcloud snap
- How to revert Nextcloud snap after failed update
- How to manage failed automatic update in Nextcloud snap
- Nextcloud snap wiki and support
meanwhile, this has been tried and tested using the snap: High Performance Backend for Talk on Nextcloud with Docker
you may want to activate Configure HPB client push for Nextcloud snap · nextcloud-snap/nextcloud-snap Wiki · GitHub
this seems to happen when federated talk sessions are accessed… is that correct?
using these too and cannot confirm your issue using snap…