I hear it too...and I think I mentioned it in an old thread...my best educated guess is it is punch-in noise...since the section is switching tempos and time signatures, I think it is safe to say that during the string overdub, they may have punched in and the string track was left up in the mix through the punch-in...
I also notice that Julius Wechter comes in a tad too early on the wood block in the first bar of the second section- it is supposed to be on beat 4 of 6 and it comes in at 3 1/2 of 6...
More likely a punch-out noise actually.
Mark