Streaming DISTANCE_SENSOR

Hi,
I’m trying to receive DISTANCE_SENSOR messages over SERIAL1.
To do this I set the stream rate of all streams to 10Hz.
I am receiving several messages belonging to the EXTRA3 stream, such as vibration and optical_flow at the right rate, yet DISTANCE_SENSOR is absent.
Stranger yet, the DISTANCE_SENSOR is showing up in Mission Planner.
I am using Arducopter 3.5.7 (b11c6af3).
In the past I used v3.6 rc7 and the DISTANCE_SENSOR message DID stream properly.
Is this a known issue?
Any ideas?
Thanks!