There must be a weakness with those servos. I had the similar problem with the Sky Surfer from Nine Eagles. In the end they shattered so much that they caused crashes.
I got a new servo from the vendor. Same problem, so I returned the model and got my money back. The N.E. I fly now, have not yet showed any sign of trouble. Cross my fingers, because it's a very nice flyer the N.E. Sky Surfer. (Sky Cruisers bigger brother