MB 157 FM borked on Arcade mode

I was surprised today when I took my MB 157 out for a spin.

As I passed 6000 meters, engine power suddenly gave out completely, the plane slowed down to 150 km/h and I had to go back down below 6000 meters to recover engine power.

It seems one of the recent patches has affected its arcade FM and the engine is simply not there after the plane crosses the 6k altitude mark.