Since nobody has responded, I think we're all dumbfounded by this problem. If it were me, I would first do an ESN change to another phone and see if for some reason it's your handset. Get any old VZW dumbphone on eBay or a garage sale or from somebody who has upgraded. Just make sure it's not a prepaid phone since PP won't activate a VZW prepay. Then use it for long enough to see if your VX8600 is the problem. I don't know how a handset could cause this, but stranger things have happened. If you have the same problem with another handset, then you're going to have to continue pestering PP customer service.