Are your missed calls in your voicemail? TMO customers (and maybe other carriers) had an incident last year with spammers who managed to dial into VM only. Fortunately, they (the spammers) were fairly dumb and started the message as soon as VM picked up, ignoring the intro. All you heard was something to do with Verizon service. Someone here explained how this can be done. Phone did not ring, and VM message icon flashed on notification.