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Auto (same as video, NDI source)
External (NEW in from v.6.2 onwards): When utilizing the External option, a channel can utilize any audio input available within the macOS Sound input preferences as the audio source. Therefore, USB audio interfaces such as the Focusrite Scarlett 2i2 are now supported. Furthermore, the Dante Virtual Soundcard can be utilized as an Audio Input option. Additionally, a delay in frames for the video pipeline can be added here. Please note that the delay option is only available when using the External Audio Input option.
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