Noise at low SPL in Bass Gear Posted October 8 · Report reply Do you hear any scratching or feel it rubbing if you gently push in on the cones? Is the sound more similar to a tapping sound or a ticking? Myself and some others did receive some 21Ipal's which were making a tick or tap type of sound. B&C replaced mine. I suspect that it comes from a loose shorting ring, but I'm not sure. It sounds like you may have the same issue.