Problem:
Baselines are not being computed correctly and the baseline_engine probe log has errors like this:
baseline_engine.BASELINE_CONFIG already has a subscriber.

Cause: 

Distributing the baseline_engine probe to secondary hubs.  One of these secondary probes can subscribe to the default queue baseline_engine.BASELINE_CONFIG and "lock out" the primary baseline_engine probe.

Resolution:
Disable baseline_engine on secondary hubs and run this probe only on the primary hub.