nHair lag and slow down... why?

[puppetsoul]

Hi all

I have some problem with nHair simulation : rondomly, when I playback, it stop on an image and lag for a while. I have to stop the simulation, what takes a long time, wait, and play it againm where it lag again 2times/3...

Notes :

• the hair is in reference

• Im on linux centos, maya2014 sp4

any idea?