VLC can't download subtitles from OpenSubtitles.org

I have a super weird problem: VLC seems to be unable to connect to opensubtitles.org.

It started months ago. Trying to download subtitles frequently got stuck on the spinning wheel (I could wait minutes without getting a result, not even "Nothing found"), but going back to the film and trying again a couple of times usually worked. However, the last few days downloading subtitles is completely dead. Today I let it spin for half an hour twice, with no result or anything progress at all.

However, if I use my computer connected to the same WiFi access point I have no problems whatsoever connecting to opensubtitles.org or downloading anything from there.

The Apple TV's network connection also seems fine. I share my movies from the routers built-in DLNA-server, with the movies stored to disks connected to the routers USB-ports.

I have tried changing the DNS on the Apple TV (to Google's 8.8.8.8), restarting the router and the ATV, but all to no avail.

The router is a high end Netgear AX 12 AX1100 with a gigabit fibre connection and everything works as expected when using my computers and phones. And the ATV, as I mentioned, have no problems streaming movies that are several GBs from the router.

Updated VLC today but it didn't change anything.