Two ways the ` take failed on the Scarlett. A record engine that had touched the input node on one device could not start after the default input moved: the node keeps the first device's format and reset() does not refresh it (-10868 from InitializeActiveNodesInInputChain). The engine is now rebuilt outright on that failure and the take retried once. And a node built in the same instant Menu Band switches the default input can answer 0 ch / 0 Hz; the start now waits up to half a second for the switch to land and rebuilds once if it never does. State: pressing ` lands on the sample backend before the take, so notes under the held key never fall through to the GM synth, and a release keeps the sample voice whenever any sample is loaded; only a first take that yields nothing restores the GM voice. Spacebar down/up now log to the debug file for the reverse-time investigation. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>