Off in viewport

[Trapezium]

I have a file with about 30 object acting as a characters hair. I've applied a flex modifier and set the flex off in viewport. Whenever set like this VRay locks up on the light cache stage in both versions *.10 and *.12 using Ma 6.

I thought it may be a bug but I can't recreate with a new file. Any suggestions other than point cache?

--Jon