I also got a call today, nobody answered. I called the number back and got a pre-recorded "thank you for calling, please wait while we transfer your call" message, after which all I heard was a bunch of scratchy noise for the next 1 to 2 minutes after which I hung up since nobody seemed to pick up.
I got no ladies with Eastern European accents, but since random people are getting called by this number, it may very well be a scam.
They called - it was silence at first, but after they started speaking in Bulgarian. They had a chance just to explain they are calling from a call company (no names, etc.?) add to ask if I make calls to Bulgaria. I did not reply... This looks like a new Bulgarian service is looking for clients...
I got a call from this number but didn't respond. Then I decided to call back, and a bulgarian lady answered saying: "Dobur den!", meaning "good day!", then I hung up. I guess I have to call back again and ask them why did they call...