Properly adjusted means the settings they have on your aids are not correct for your hearing loss. The Frequency adjustment doesn’t fix that fundamental problem, it just puts a band aid on the problem. You don’t have enough 2k to 4K at soft sounds, which is 50db, or maybe also at normal sounds, which is 65db. Best start with soft sounds first, and I would try 3K to see if the “s” sounds improve. The simple thing to do is to turn up the volume at those frequencies for all bands, but since you seem to have problems only with soft sounds, then just change that.
Most Costco audiologists have a real time analyzer. Have the audiologist run a real time analysis test on your aids and make adjustments “live”, and test the new adjustments with real world sounds, to make sure it works for you. This is important: Before the test is run, turn off all sound processing on the aids. Anti feed back, noise suppression, speech enhancers, etc. These are active and will interfere with the test. If the sound is muddy at louder volumes, then the limiters, on hearing aids called MPO, are too aggressive and they need to be reduced. Then usually the overall volume turned down a little.
I suspect you may be working with an audiologist who doesn’t know or does not want to, The warning of " Don’t want to make the aids too loud, seems to reveal this. What should be done is to find the problem areas and sort them out. work with the EQ settings on the aids. If the get balky, then ask them to call the hearing aid maker for tech support. Costco offers unlimited follow up adjustment visits, so stay on them until your aids work for you.
Drat - i tried to attach a consonant pitch chart to this post but it would not so it. So google the phrase and use this to help you communicate your problems with speech to the audiologist.
But try this one:
from the general search of