Motors dying as they are being calibrated

I’m currently using a 3 cell 5000mah LiPo batter. The battery connects to the 3DR Power Module, which connects to a wire harness power distribution. This PD connects to each of the ESCs which connect to the motors.

This problem wasn’t happening before and only started last week:
When I’m calibrating the motors, or just checking the throttle after arming, eventually all the motors except 1 stop spinning. I use the voltage checker on the battery and it says it still has 10.6/11.1 V left.

I don’t understand what could be causing it. We charge the battery for only a few seconds and it seems to fix the issue, but eventually it happens again. Any ideas?

Do you get any beeping noise coming out from the dead motor? Or anywhere else?

Are your ESCs getting hot, is motor timing correct and so on. What all tests you have made?

Have you tested one motor at time with separate ESC…

I’ve calibrated the motors one at a time. They do the appropriate beeps (Musical tone when connected followed by two beeps to indicate throttle is high. Then when the throttle is low, 3 beeps; 1 for each battery cell. Finally, a long beep). Then they would spin based on the throttle stick position like usual.

The problem is right after, where after a few seconds, the motors slow down then stop. This is with the throttle still high. No beeps and no extra heat. The temporary fix seems to be charging the battery for a few seconds but it happens even when the batter has 10.6/11 volts left