Hi,
lately I've been having problems with my quad (Flamewheel 450, Naza+GPS, Jakub 155mm landing gear+gopro+gimbal).
I was getting about 6mins flight with 4S 4000mAh lipo, but I wanted to add FPV Tx and OSD, and my quad apparently became too heavy.
It would start to blink red light and autoland...