pavucontrol running halves reported latency
When pavucontrol is running, it creates monitor streams to everywhere, whose ports have all Latency fields set to zero.
This affects latency reporting: pw-dump 71
(id of paplay node) when pavucontrol is not running:
"Latency": [ { "direction": "Input",
"minQuantum": 1.000000, "maxQuantum": 1.000000,
"minRate": 512, "maxRate": 512,
"minNs": 0, "maxNs": 0 }
],
and when pavucontrol is running
"Latency": [ { "direction": "Input",
"minQuantum": 0.000000, "maxQuantum": 1.000000,
"minRate": 0, "maxRate": 512,
"minNs": 0, "maxNs": 0 } ],
pw_get_time_n
calculates the delay by taking the average of max+min, so it is halved when pavucontrol runs. This then affects all clients and also eg. pulseaudio latency reporting.
There probably should be something in the port latency calculation so that it ignores e.g. stream ports that don't have valid defined latency.