Split a channel's patch set by the one-physical-input rule
(2026-08-07-one-summing-bus.md §3c): the FIRST physical input is kept, any later one is
dropped, and soft sources always ride along — an application stream owns no preamp, so a
strip carrying a browser beside a mic is a playback channel, not a summed patch.
This exists because the patch DOOR is not the only way a set reaches the engine. A stored
session and the stage-change recompute both drive addChannelSource directly, so a document
written before the rule would otherwise restore a state the door now refuses. They report
what they dropped rather than dropping it quietly: losing an operator's patch in silence
mid-show is the failure the restore path is written to avoid, and a line in the log is the
difference between a rule and a disappearance.
Split a channel's patch set by the one-physical-input rule (
2026-08-07-one-summing-bus.md§3c): the FIRST physical input is kept, any later one is dropped, and soft sources always ride along — an application stream owns no preamp, so a strip carrying a browser beside a mic is a playback channel, not a summed patch.This exists because the patch DOOR is not the only way a set reaches the engine. A stored session and the stage-change recompute both drive
addChannelSourcedirectly, so a document written before the rule would otherwise restore a state the door now refuses. They report what they dropped rather than dropping it quietly: losing an operator's patch in silence mid-show is the failure the restore path is written to avoid, and a line in the log is the difference between a rule and a disappearance.