I ported a number that I had from skype over a year ago.

Ive noticed that once the "subscription" on the number expired, I started having these type of problems. But they stopped. VoipO CS helped with the porting, of course. I did ask them about this and they assured me that only one person can "own" the number at a time.

Been wondering if skype somehow resold the number even tho it's been ported.

It certainly would explain things though.