Help regarding sudden throttle drops after approximately 10 seconds of flight

We’re using a Jellyfish frame, and were planning on doing some PID tuning but noticed that not only was the UAV unstable (to be expected) but it read throttle instantly going to 0 after about 10 seconds into flight - consistently.

Corresponding Log:

The log also includes a video of the crash. We’ve double and triple checked the controller and communications, and it is suddenly reading 0 throttle after 10 seconds no matter what we do.

Any feedback on what could be going wrong?