Mike, I received a call this morning from the same number and no message was left.

Caller ID is "N SHORE MKTG"
On Call Back the line rings but no answer. Likely a sales call but could be a misdial. Until there are more reports of calls from this number I guess we are in the dark as to the source and purpose of the call.

9/30/13 8:30AM PDT

Got another call from the same ID but different phone number. Looks more and more likely it is a ROBO Call.

N SHORE MKTG     781-324-0427    09-30-2013 3:30 PM
Earlier call:
N SHORE MKTG     781-324-0312    09-30-2013 8:38 AM

Still no message, just a hangup.

I think I've found the source of these calls.
http://www.merchantcircle.com/business/North.Shore.Marketing.781-322-1224

Seems like they are in the TV Guide renewal (or rip-off) business, a comment on their web page is:

"This company conducts telemarketing calls, ignoring 'do not call" lists under the guise of attempting to get folks to re-new TV Guide subscriptions, Completely unreputable. "

If you have subscribed to TV-Guide they (TV-Guide) can legally call. This seems like a different company representing themselves as TV-Guide, just a guess.

A second comment states:

"A comeon to renew TV Guide @$1.99 which is really $228.00(for 114 issues which is not explained until after you accept offer)........... a very sneaky marketing plan..........people are paid for this practice?. "

A good company to stay away from!

Several calls from N Shore Mktg within 24 hours. No message. additional numbers: 781-322-0024,  781-324-0472

Called left no message.  Blocked number.