I received the same "one ring, anonymous call" shortly after I made an online pmnt for an application fee. It's interesting you would mention PayPal because that is the method I used. Maybe there is some connection.
Here it is nearly a year later since this thread starting and this is still going on with THIS number, among others. I get one of these calls EVERY TIME I add more minutes to my Net10 Pre-paid phone. We use CALLINGMART.COM which is a third party sellor of minutes, and we pay by PayPal so these INDIAN SCUMBUGS cannot get our credit card info. Put minutes on two days ago; BAM! Call today. This pattern has been repeating for YEARS. So, I KNOW it is ONE of these two INDIAN companies: NET10 or CALLINGMART. I HATE doing business with them, but its the cheapest thing available in our area, other than doing business with Walmart, whom I also hate. REFUSE to use Verizon or AT&T or the other 'large' carriers.
Call Type: PHISHING SCAMMER/FRAUDSTER/THEIVES
Caller: CALLINGMART.COM or NET10