Many custom and receiver-in-the-canal hearing aids have tiny filters which are designed to protect the receivers (speakers) from debris such as cerumen and dried skin. Eight out of ten of the calls I get about dead aids are related to plugged filters or guards. This means the little bugger did its job. But how to replace them?
The guards are usually found on the end of a plastic stick. On the other end is a removal nub which is placed in the old, dirty guard to remove via a clockwise quarter turn. Then you invert the stick and insert the new filter in the receiver opening, this time lightly pressing and quarter turning the stick. Discard the stick. Your audiologist or dispenser will demonstrate this for you. Some manufacturers have tutorial diagrams that accompany the filters though they tend to confuse many.
How often should you replace the filters? I make different recommendations per patient. It really depends upon how much ear wax you make. Some folks have to change the filters out every other week. Most are good with a monthly switch out. Look at the filter - not always an easy task due to its size - and see if it appears yellowed or otherwise plugged with debris. If you wear a receiver-in-the-canal (RIC) style device you may have to remove the dome tip to see the filter. This in itself can be a test of your dexterity. Having a magnifier and a well lighted table on which to carry out the task is the best scenario.
In between filter replacement, use a brush (can be a toothbrush) or better yet, the single row brush/wire loop tool that your provider can give you. Daily maintenance will prolong the life of your expensive hearing aids.
And for pete's sake, don't store the aids in the bathroom or kitchen or anywhere moisture is prevalent.