Three fixes from a day spent reading a live server's logs rather than its source.
The idle saver was switching the radio off underneath people who were watching. A receiver parks itself when nobody is listening, and the check for "is anybody there" was written out by hand in three places — only one of which counted the second and subsequent spectrum viewers. So on a shared receiver, a park scheduled while everyone was away would fire minutes later on top of viewers who had since arrived: the waterfall freezes, the client reconnects, and the radio is simply asleep. Measured at 25 occurrences in 36 hours on one Pi. It shows up most on multi-listener servers and most when a client is idle or backgrounded, because that is exactly when it holds a spectrum socket and nothing else.
Connections now record what they actually delivered. Every disconnect reports how long it lasted and how many bytes went down it, with audio and spectrum counted separately — so a nine-second visit that carried 40 KB of waterfall is visibly a person having a look, and a nine-second visit that carried nothing is visibly a connection that never worked. Those two used to log identically. Counting them apart also shows a listener who has minimised the page: the audio keeps flowing while the spectrum stops, which duration alone cannot reveal.
The admin page's connection history shows Data and Drops. The byte totals were already being recorded and simply had no column; drops were not recorded at all beyond the live view, and now survive the listener leaving — which is the point of a history. A session that delivered plenty and dropped steadily is a link that could not keep up; one that delivered plenty and dropped none is somebody who left. Zero data is marked in red: it is the only value in that table that means something went wrong.
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