Raytraced display mode restarts over and over again

Dear all,

since the last update (7 SR6) raytracing display mode restarts over and over again in a various interval between 5 and 20 seconds. Anyone else experiences this? Is it a bug or a feature?

thanks
Cyana

Ok, I restarted Rhino and raytrace display mode turned to working normal again.
Thanks anyway
Cyana