Is this stalking?

An ex-N, who I have had NO CONTACT with for 4 years, calls me at work (the only number ex-N has for me, I changed my home and cell numbers 4 years ago), and plays songs with love lyrics on my voice mail. The longest time in between calls is 3 months. I have received 2 calls this week.

IT'S BEEN 4 YEARS OF NO CONTACT ON MY PART!

I am disgusted and want to scream every time I get a new song. I want to be left alone! I refuse to be afraid. I refuse to make any contact. Something tells me that I should be concerned. Is this stalking? It's just attention seeking, right?

4 years ago this sicko WAS sitting outside my home. That was clearly stalking. One day I politely walked to the car and said please leave me alone, we will never be friends, I am not angry but I want you to go away. It worked! Well, except for the stupid musical messages!

What to do?