DJM 700 Record out problems

Why are my recordings slow when I use the record out on my djm700?  I recorded a few dj sets at 128 bpm and they then play at 118 bpm?  When I use the booth out they are correct?  What gives, my mixer is one year old, everything works perfect, but my mixes are slow.  I am using Audacity and an alesis i02 audio interface.  Please advise, thanks.