Had the same problem with subsonic as media provider my “fix” for subsonic was to:
Manage offline files → Download queue → Remove all → Restart the download (in my case a playlist)
I used nextcloud as the server with the music app which supports a part of the opensonic standard. As WebDav supports multiple artists i switched.
If i try to bulk download my collection it slows down after a while. In the download queue i can see this message “waiting before retry - Socket is closed” (“Queued - Socket is closed” and "HTTP error:416). Can i do something to fix this?
One solution could be that if multiple files in the download queue have the status “Queued - Socket is closed” it doesn’t change to “Waiting before retry - Socket is closed”. I think the main slow down is the “waiting” part not the connection.
There’s no socket issue in those logs, just the normal error 416 because your server does not support it and it recovers.
In all cases this sounds more like a server side issue, you can limit the number of simulatenous downloads or disable http2 to try to workaround your server.
As a question if WebDav is the media provider and the tags get scanned get the files “downloaded” from the server to extract the info or how does this work?
If they get downloaded for the metadata extraction and in the options for webdav “Automatic media offline cache” is checked it should be possible to save them directly instead of discarding the downloaded file after the tag extraction only to download them again after this.