Hello,
I am facing some issues with my new Pixhawk Pixhawk 4. it works amazing after setup but after few minutes it shows I/O error and GCS is unable to connect that board and nothing will perform. I tried with both Ardupilot & PX4 firmwares.
Thanks!
Try putting the bootloader on again.
Flash the chibios ardupilot bootloader on it then the PX4 one.
If it doesn’t fix it, assume it is hardware.
I did it, it’s working but after flashing any firmware same problem occurs within few minutes.
New hardware then. Something is wrong
Last thing you couldn’t try is flash firmware on there and out a different vehicle on. See what happens. otherwise new hardware.
I did it but getting same issue again and again. I test all the possible things like different firmwares, different frame type & even I didn’t select any frame still the same problem occurs.
I got frustrated with this hardware. 
