Voice Distortion

I am new to this forum. All sounds seem to resonate in both ears with or without hearing aids. The best analogy is that voices sound like they are coming from a kazoo. Several ENT doctors and audiologists cannot seem to agree or pinpoint what my problem is. Anyone with similar symptoms or possible answers?
The resonating is constant and no 'trigger" event. My audiogram has a decline at the higher frequencies level in both ears. I have tried the latest technology in several hearing aid models with not much improvement. Audiologists have tried various settings with no success. Is there a name for my condition that I can do further research? I also have low level tinnitus (sort of low roaring sound) but it does not really bother me. However, it may have some effect on the resonating.