Beats Electronics urBeats User Manual page 53

UK English
Eartip Fit Testing
A good way to gauge whether or not the eartip is sealing properly in your ear
canal is by snapping your ngers right next to your ear. If the seal is correct,
your ear will not feel "plugged", yet the snapping of your ngers will sound dull
and distant. If you hear your nger snaps distinctly, the seal is probably not
adequate. If the sound of your nger snapping is dull and distant, but your ear
feels plugged up, like you're on an airplane preparing to land, then you've
over-inserted the eartip.
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