Strange Actuator Outputs

One of my Tarot X6 drones is exhibiting a strange actuator output signal. Normally, the actuator outputs center around 1500 usec, and never hit the upper or lower extremes. But I’m now seeing the center somewhere aroung 1200-1300 usec. Take a look at the plots below.

This is what it usually looks like.

This is what I’m seeing now.

I’m using PX4 v 1.13.3

Does anyone have any idea what is happening?

Thanks,
Joe