It's possible to assign the Click to the Headphones output(s) only. Doing this prevents the Click sound from being sent out of the main outputs. Here's how to assign it:
1. Press the SETUP button.
2. Press the PAGE UP button to confirm that you're on "SETUP page 1."
3. Press the F1 button (OUTPUT).
4. Press PAGE UP or DOWN to select page 2 ("OTHER OUTPUT").
5. Press F1 (MASTER).
6. Press the cursor right button to highlight "CLICK."
7. Turn the dial counterclockwise to move the indicator to the PHONES line only.
8. Press the KIT button when you're finished. The new setting is saved automatically.