I received a call just after 1pm on a Sunday. By the time I got to the phone it had kicked over to voicemail but they didn't leave a message. So after a little research they're either some sort of fraud or market research company. Either way it's a robo-call that is quite annoying to stop what your in the middle of to answer the phone.
Four calls in two days! Two calls last night at 6 and 8:09pm; two calls again tonight at 4:58 and 8:59 pm! Picked up on the 4th call, ready to rip some head off but waited and didn't say anything. Heard nothing, no recording, no person so after several seconds I hung up. Adding this sucker to the blocked caller list.