Email support@auduo.app. Include your macOS version, your Mac model and which two outputs you were using — that is usually enough to reproduce anything. Settings → Advanced → Copy Debug Information puts all of it on the clipboard at once.
Launch Auduo once and it restores your previous output by itself.
Settings → Advanced → Reset Audio Configuration. Auduo only ever removes its own device, so anything you built yourself in Audio MIDI Setup is left alone.
A Bluetooth device that reconnected may need Reconnect from the menu.
Every Bluetooth device has its own hardware delay, often 100 to 250 ms depending on the codec. Auduo keeps the outputs from drifting further apart, but it cannot align their absolute delay yet. Settings → Sync → Play Sync Test lets you hear the offset.
macOS gives an aggregate device no master volume, so the keyboard keys have nothing to act on. Use the sliders in the menu bar; the master slider scales them together.
Two devices need at least one sample rate in common. A 44.1 kHz-only device paired with a 48 kHz-only one cannot be grouped, and Auduo says so rather than failing quietly.
It only works when Auduo runs from the app bundle in your Applications folder.
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