[Maine-birds] mystery singer

Hi, I have several somethings dueling it out on my yard, unfortunately when I go looking they clam up.  I've kind of run through the usual suspects and come up empty.  If anyone can identify the bird making the 'ka-bink' type call in the video I would be very appreciative. 
  I put it on th farm page so I think everyone can see it.

Sarah

https://www.facebook.com/pages/Mountain-Valley-Farm/226253457513379?ref=hl