i got a call too on Nov. 21, 16 at 330 pm.   They left no message and I USED to get A Huge Amount of scam/telemarketer type calls but not in the last year or so.   I sure hope it isn't all starting up again - and although this sounds highly implausible, i still feel the need to put this out there:
    the only thing 'different or new' I've done with/on my phone was downloading this app last week:  Scanner Radio
was wondering if anyone else just did the same before these calls.  Like i said unlikely but still ya never really know anymore.
peace!