[SOLVED] Doubt for a peer with strange access

[san.lostsoul]

Hi everyone, I'm asking because I can't figure out something that's been happening to me for a few months. Every now and then, a peer from America, with an IP ending in 167:6666, connects but doesn't pass through. The app version is Unknown [....x...0..ax..] or something similar, only on a single file. I change my line's IP address, change the listening port, nothing, it reconnects, same IP and port. So I delete the file and that's it. After a few hours or days, it reappears, same IP and port but different file. Has this ever happened to anyone? What could it be traced to, a tracker? The PC is a Linux Lite 6.6 that doesn't do anything else, so it has nothing to steal, but it seems strange to me. Thanks.
Edit: more than one, now!

[san.lostsoul]

Well, I think I found a solution, whatever it was. I disabled uPNP and forwarded the PC's IP directly with Deluge. This almost blocked those connections and also allowed it to detect the external IP, which it didn't do before. And it's also faster. HTH. Regards, everyone.