Hey @francisdoody Where do you host your NextCloud instance? I’m having a similar problem, but I know for sure it is because of a slower server I’ve rented out. Might be a similar reason for you too?
When I upload a GoPro footage to nextcloud and play it with the web player preview it only plays after it fully streams it, GoPro footage of 2GB will takes ages until I can watch it.
When I upload a non GoPro mp4 with 2 GB is plays straight away and streams as I go.
The playback issue is because your system is low spec and unable to handle streaming large files. Was hoping there was more to your very vague post. It helps to keep topics separate + include technical details so others don’t have to ask for them or get confused.
You’ll need to upgrade your machine to improve video playback of large videos. Or you can sync them to your machine using the desktop/mobile app and watch them locally.