ER•4 MicroPro Earphones have special filters that shape the frequency response and prevent earwax from entering the earphones. These green filters are located in the end of each earphone and are visible when the eartips are removed. A dirty filter will reduce or block the earphone output (a filter may be blocked without appearing to be dirty). If one or both earphones stops working, or if the volume decreases, the filter should be replaced. The frequency with which the filters need to be changed will vary widely among users.

To check: Remove the filter. If sound returns, insert a new filter.

Note: Filters are not reusable.

Removal 1. Remove eartip. 2. Insert tool into     the filter. 3. Remove filter.     Discard old filter.     Filters are not     reusable.

Replacement 4. Insert a new filter     and press gently     against a hard     surface to secure     it in place. 5. Re-attach eartip.