WMUR/UNH is not a reliable poster.
Their House polling has been all over the place this year, and has been prone to wild swings. First they had CSP up by 16, then Guinta up 6, then CSP up 9, and now Guinta up 3.
And just recently, they had Kuster expanding her lead on Garcia by 14. Something with their methodology has been very, very wrong, and they haven't bothered fixing it. Disregard all UNH polls.
Maybe that's because New Hampshire is prone to wild swings? WMUR is the most reliable pollster in the state.
One-fifth of NH voters aren't that fickle.