HeartBeat loss after configuring camera

I am using pixhawk FC om px4 version 1.10.1 with an onboard computer connected through serial.
my software works alright until I configure camera.
after camera configuration I get disconnected and connected repeatedly every few seconds
my camera parameters are:

Trigger mode: Time based, always on
Trigger interface: Seagull MAP2 (over PWM)
Time Interval: 40

thanks