I get calls from this number daily - 301-882-9950. It says RECEIVABLESPERF on my caller ID. They leave no message, if you answer after four or five rings, you get a dial tone, but if you answer after one or two, you get that annoying pause before someone says anything. I just hang up. I tried calling back, but the number is not in service. I'm goingto try the silence bit, and see what happens. When I get sombody, I'll tell them that I'm Sergeant so-and-so from the local police, and that the call has been traced. See what happens then.
I just called this number again - when I used redial to call it back I got a not in service, but when I manually dialed it, a woman named Morgana answered and said "RPM". I asked why I was getting called, and she said, "wait a second", and looked up my number. She said, "Hamilton Dental Associates?", and I said no, that's not me, and she said she will remove my number from her list.
Call them up, and ask for Morgana, and give them a hard time - back them up against a wall, and see how fast they back off.