Devices
Settings → Devices configures the audio and MIDI hardware that LTCast uses for input and output. Set these before the show so every signal goes where you expect. The rows appear in this order.
LTC channel of the file
The first row, LTC Channel, reports what LTCast found in the loaded song — LTC detected on CH n and LTC OK / LTC WEAK, or LTC not detected. Below it, LTC Track says which channel of the audio file carries its LTC: Auto-detect (CH 1/2) scans channels 1 and 2 and locks onto whichever decodes first; choose CH 1 to CH 4 to force it.
Music output
Music Output — the audio device for the music, Default being the system default. Beside it, Stereo (pair) sends left and right across a channel pair (CH 1/2, 3/4, …), while Mono (single) folds both into one channel so you can put the music on any single channel and leave its neighbour free. The channel pills choose the pair or channel. On a multichannel interface a typical setup is music on CH 1/2 to the speakers and LTC on CH 3 to the timecode device. Pills beyond the device's channel count are greyed out. Music volume and pan are in the music strip of the main window, and do not change the LTC level.
LTC output
LTC Output — the device that carries the LTC signal. The first entry, Muted (decode only, no audio out), is the default: LTC is still read for display, chase and triggers but nothing is sent. Choose a virtual cable (VB-CABLE on Windows, BlackHole on macOS) or a hardware interface to send LTC. The CH pills beside it select one or several channels to carry the (mono) LTC; with none ticked, LTC is muted. The level is set in Settings → Outputs. See LTC Audio Output.
LTC input
LTC Input Device — the audio input that carries external LTC for Chase and TC Bridge; None by default. Next to it, the channel menu offers Auto-detect (parallel), which listens on channels 1–4 at once and locks onto the first that carries LTC (the one it found is shown as Auto → CH n), or CH 1 to CH 4.
On first access, device names may appear as generic labels rather than real hardware names. Click Grant microphone access to trigger the operating system's permission request; after that, real names — including virtual cables such as VB-CABLE Output or BlackHole — appear. This is a one-time request per machine.
Microphone permission is needed to list audio input device names on macOS and some Windows configurations, even when the input is a virtual cable rather than a physical microphone.
MIDI output
MTC Output (MIDI) — the MIDI port that carries MTC and MIDI Clock; a status dot and Connected / Disconnected show whether it is open. On Windows, create a virtual port with loopMIDI and select it here; on macOS use the IAC Driver (enabled in Audio MIDI Setup). A hardware MIDI interface also works if you need to send MTC to a physical device. The MIDI port for triggers is set separately, in Settings → Outputs.
MIDI input
Below the MTC port, MIDI Input selects the port of a control surface or other device that is allowed to drive LTCast, and MIDI Mappings lists what each of its messages does — play, stop, next song, GO. See MIDI input (remote control).
A short help text at the bottom reminds you which virtual device to install for your operating system.