Personally I would run the cable behind the seatpost, in front of the canti hanger -ish and use a greater angled (though actually shallower) noodle (and tweak the angle to give best results) .
I would check the cable outers not setup to see if they slide through very smoothly.
I would check the V's have no index feeling to them when not connected.
I would check the canti/v setting mentioned, though it's not actually a Canti setting (they have a big warning in the instructions) but it's a modulation/power setting as per Avid/Deore LX
So tune it to less power/modulation but to a firmer feel, finger strengthener setting.
M900 are nice canti's
PDF has been saved and thanks, I'll have a poke with the red "slow dial", M900s are nice
EDIT///. grabbed the instructions for you.http://cdn.sram.com/cdn/farfuture/nkxby ... _07_99.PDF