COMMAND_ACK not sent?

Hello all - I’m trying to communicate with a Pixhawk running PX4 firmware. I’m communicating fine, getting heartbeats and telemetry fine. However, when I issues commands I’m not getting the ack back:

If I throw arudpilot on the pixhawk, I get these ACKs no problem. I feel like I’m missing something - like it needs to enabled somehow / somewhere for the PX4 stack to issue ACKs. Anyone know?

Does anyone have any experience with this? Is the PX4 firmware setup to not ACK commands?

It should ack the commands. Which command did you test?