I have downloaded the WWDC signal generator example code for 2019 session 510 "What's New in AVAudioEngine."
at link
When I run it in XCode 13.2 on OSX 12.3 on a M1 Mac Mini , on line 99
let mainMixer = engine.mainMixerNode
I get 9 lines
2022-03-30 21:09:19.288011-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288351-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288385-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288415-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288440-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288467-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288491-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288534-0400 SignalGenerator[52247:995478] throwing -10878
2022-03-30 21:09:19.288598-0400 SignalGenerator[52247:995478] throwing -10878
in the console output.
-10878 is in valid parameter
But the program seems to run as expected.
Can this just be ignored, or does it indicate improper setup?