Strange entries in Report manager

Not sure what the story behind this one is, but i seem to be getting a lot of random entries appearing in my report console on FreePBX.

see here for screenshot : http://www.fluxbox.co.uk/Images/unknown.png

Not sure whats causing these, anyone got any ideas ?

The IP Address they are coming from (Channel SIP/86.20.***.***) is the actual external IP of the Asterisk Server, as you can see the source/destination numbers seem quite random, but the status reports they are answered calls (although only for seconds)…

Hope someone has a clue, cus im pretty confused by an PBX calling itself lol