[dinnygun]

I have Kodi running on a Raspberry Pi. On about the 17th August is started uploading to ftp.rrze.uni-erlangen.de, which I see is a Kodi mirror. I noticed this 2 or 3 days after it started, during which time it had uploaded some 125GB.
The unit is located in Australia, but I am currently in Europe, so I had someone disconnect the power to it, as my initial reaction was that I had been hacked. Now I realise it is a Kodi mirror site, I suppose there could be a less sinister explanation.
Unfortunately I don't know a version, although it is fairly recent (6 -12 months since I checked the version, but it has hopefully been auto-updating).

It looks like it was establishing an https connection and sending about 1.3MB about 10 times a second.

Can anyone offer a suggestion as to what was going on?

[Karellen]

On about the 17th August is started uploading to ftp.rrze.uni-erlangen.de, which I see is a Kodi mirror. I noticed this 2 or 3 days after it started, during which time it had uploaded some 125GB.

Kodi does not upload.
Can you create a Debug Log that captures this?
Possibly you have 3rd party addons installed that could be of a concern. Banned Add-ons (wiki)

[dinnygun]

Thanks. I'll have to wait until I get back to Australia to check the log. 
As for add-ons, I think the only one I ever put on was for subtitles. Again, I'll check that in a few months.