Cannot persist subtitles

I know that this issue has been discussed many times but I couldn’t find out why it’s not working for me. I’m trying to have subtitles persist once I download them (so I don’t have to download them again when I want to watch another time).

In Settings I’ve got it set to save subtitles next to the video. The video folder is owned by ‘kodi’ user and when I download them I can see them appear correctly in the video folder but after a second or so the file disappears again.

When I set Custom subtitle folder in the Settings I’m getting “Cannot download subtitles” error every time I try to download any subtitles. It’s not a problem with privileges – again the custom folder is owned and writable by ‘kodi’ user.

I’m using Raspbian and repo Kodi 17.1.

Any ideas?