Hello everyone,
I set up a custom Anki server following the guide in the Anki manual, and I would like to ask for help with a media sync issue I’m having.
The server seems to be functioning “well”, as I was able to log in through my AnkiDroid device without any problems. I copied the profile from ~/.local/share/Anki2/user to ~/.syncserver, and everything appeared to be in order. 
After syncing, AnkiDroid displayed a message saying “Full sync from server”, but this process completed very quickly. Since I have thousands of media files in collection.media that are also in ~/.syncserver, I suspected that the sync wasn’t complete.
When I tapped sync again, it felt like the process was more focused on uploading changes instead of downloading those media files. I tried doing a forced one-way sync, and even though it showed “Downloading” and then “Checking downloaded file,” it ended up saying “Media synced,” which was probably incorrect.
In the settings of AnkiDroid, I have the following configurations:
Fetch media on sync: Always
Allow sync on metered connection: Enabled
On the server side, I also tried setting MAX_SYNC_PAYLOAD_MEGS=1000
Server is run by the command: SYNC_USER1=user:pass anki --syncserver
Despite these settings, the media files are still not syncing. (All decks are synced)
I would really appreciate any guidance on what else I might check or adjust to help resolve this issue. Thank you so much for your support!