Midi in stoppage

[canzil]

Hello Friends
I no longer know what to do, I have a problem and don't know if it's the traktor or is OSX. I have a rMBP late 2013 with Yosemite 10.10.1 and use traktor 2.7.1 with all updated drivers. Currently I use 2 x1 mk1 in MIDI mode with my mapping, and what simply happens is that the IN signal simply stops working, but out (LEDs) continue to receive; to return to work I need to remove the cable and put back in, but in a gig that happens about 10 times in 1 hour, it's not acceptable.

What I already try to solve.
Format my mac and do a clean install - not solve
Change over 10 USB cables (not kidding) - not solve
Change the USB hub - not solve
Try install old versions of traktor 2.6.8, 2.7.1 and 2.6.2 - not solve
Test with x1 of a friend (same problem) - not solve
Try install old drivers of x1 (2.7.0 / 2.6.0 / 2.5.1) - not solve

So somebody already have this issue?
Seriously I suspect this is a OSX bug, but I can solve it.

Wait some help
Thanks in advance

[SlvrDragon50]

JK. Not sure man.