They just started calling me, I am having the same results. They call ring two to three times, hang up, never leaves a message even when I send the call to my voice mail. Calls like this make my want to bash the callers head in with a sledgehammer and I just happen to be going to Texas in the morning.
It looks as though my first call came around 2:00 PM on Feb. 3rd, then Feb. 4th, 5th, 6th and 7th around 9 AM. Took Sunday off, then called again today at lunchtime, 12:29 PM. It will be interesting to see how long this keeps up. No message left.
I only discovered these calls because today I happened to have a remarkable 15 calls from 8 unknown numbers which I discovered on my call log, none of which rang because I have my phone set to decline all numbers which are not on my contact list.