Is it Manufacturing error or any power electronics error from my side

Hi community, I am using pixhawk 2.4.8 purchased from banggood.in it was the second autopilot. the first pixhawk had imu problem that I figured from data logs and replaced with used pixhawk from my other quadrotor. meanwhile, I purchased a new one and replaced it with the old one. this one also seems to have the same problem the quadrotor just gains throttle abnormally and crashes on to the ground. I don’t understand if I again brought faulty pixhawk or I am doing some other mistake. attaching data flash logs. please help

found out that in both faulty pixhawks, one of them had power port not getting 5v supply and other on ADC port. this has lead to faulty performance of the pixhawk. when i compared port readings with the pixhawk that is working fine. I suspect a diode might be a faulty one in manufacturing these pixhawks. hope i purchase from good pixhawk supplier from now on.