Here are the console logs for the failure case standard 13:07:40.422508+0100 CarPlay connected session <CARSession: 0x600003404500> configuration: [<CARSessionConfiguration: 0x12da05010> name: (null), modelName: (null), manufacturer: (null), serialNumber: (null), transport: USB, ETC supported: NO, right hand drive: NO, limitableUserInterfaces: (), manufacturerIconLabel: OEM, manufacturerIconVisible: YES, night mode supported: NO, supports AC_BACK: YES, screens: (     "<CARScreenInfo: 0x600001640370>, identifier: PurpleTVOut, availableInteractionModels: Touch, Knob, Touchpad, primaryInteractionModel: Touchpad, isLimited: NO, isNightMode: NO, supportsHiFi: NO, maxFPS: 0, physicalSize: {w: 0.000000, h: 0.000000}, pixelSize: {w: 0.000000, h: 0.000000}, wantsCornerMasks: NO, initialFocusOwner: YES, viewAreas: (\n    \"<CARScreenViewArea: 0x600001044500> {visibleFrame: {x: 0.000000, y: 0.000000, w: 1024.000000, h: 1024.000000} safeFrame: {x: 0.000000, y: 0.000000, w: 1024.000000, h: 1024.000000} displaysTransitionControl: 0 statusBarEdge: 0 supportsFocusTransfer: no}\"\n)" )], [CC] Now Playing Album Art Mode: Unknown, [CC] User Interface Style: Automatic, [CC] Additional Safe Area Insets {top = 0.000000, left = 0.000000, bottom = 0.000000, right = 0.000000}, [CC] Dashboard rounded corners: {top = 0.000000, left = 0.000000, bottom = 0.000000, right = 0.000000}, night mode: unset, limit UI: unset, ETC available: unset standard 13:07:40.427308+0100 CarPlay Template scene content style updated to dark standard 13:07:40.427956+0100 CarPlay [0x600000a7dc70] Initialized with scene: <CPTemplateApplicationScene: 0x12e705510>; behavior: <_UIEventDeferringBehavior_CarPlay: 0x6000021e8c00> standard 13:07:40.428045+0100 CarPlay 0x600002fd1590 setDelegate:<0x6000021e8fc0 _UIBacklightEnvironment> hasDelegate:YES for environment:Car[2-7]:ch.CarPlay.CarPlay standard 13:07:40.428298+0100 CarPlay Application declares audio entitlement. standard 13:07:40.428313+0100 CarPlay Connecting to listener endpoint for scene identifier: Car[2-7]:ch.CarPlay.CarPlay standard 13:07:40.429475+0100 CarPlay Scene will connect observer fired standard 13:07:40.429487+0100 CarPlay Attempting to deliver interface controller... standard 13:07:40.429497+0100 CarPlay App ready to receive interface controller standard 13:07:40.429507+0100 CarPlay App does not support any CarPlay template connection

Hi thanks for the reply I am now able to join a channel, record an audio, but am not sure how to trigger the didEndTransmitting call, i.e. what needs to happen after recording (and transmitting the audio file to the server backend)? thanks Marco