I cant seem to get MLAT targets on my map

My site:

It appears that I feed MLAT data, as best I can tell, but I can never, ever…see MLAT traffic on my 1090 screen.

Where do I start to debug this?

pi@piaware:/usr/share/dump1090-mutability/html $ sudo piaware-config -show
contents of piaware config file ‘/root/.piaware’:
mlat 1
mlatResults 1
mlatResultsFormat {beast,connect,localhost:30104 basestation,listen,31003 beast,connect,feed.adsbexchange.com:30005}
password xxx
user gemohler

Check that dump1090 is configured to listen on port 30104 for Beast input data.