Remove filters on queue (if any).
filter on queue per ready message desc
See that there are plenty of queues with uuid names with quite some unacked messages.
At least one has almost 1Gb of message as of now (a213366e-0021-34d9-87f6-e1a57b03b8dd).
The main queue of the listener is consumed from.
So that might be nothing and simply stopping the subscription to that queue somehow would be enough.
I'm not sure.