Aphex IN2 - Manual (Page 8)

At the bottom far right, click on the I-O icon.
The default set provides 2 MIDI tracks and 2 Audio tracks.
Find the audio track called 3 Audio.
The default should show AUDIO FROM EXT In, input 1.
Under MONITOR, click on AUTO.
The Master Output should show 1 / 2.
Click the red track arm button and you should be able to hear yourself in the
headphones or speakers.
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