I'm experiencing the issue as well. No ring, just a straight voicemail notification.
Also, has anyone experienced their data connection freezing up? Every once in awhile, my data won't load anything and the signal indicator always shows one circle and LTE. A quick switch to airplane mode and back fixes the problem. Full bars and working data again. Strange.
Verizon iPhone 5
This happened to me a few days ago. I was out with my family (battery was around 50-60%) and I checked in with Foursquare. I put my phone back in my pocket, took it out 30-40 minutes later, I was down to 12% with the little circle indicating I didn't have service.
Meh, it's beta.