acoustic feedback that’s very strong but maybe an octave higher than the user can hear. Quite an onslaught on the cochlea! Been there because of an ill-fitting mould. Excellent audiologist sorted that AND rolled off the high end to match my hearing cutoff - so if ever there’s a whistle it falls within a pitch that I can hear.
A similar problem, as I described earlier—maybe it’s a broken balanced armature in the receiver.:
Are they BTE pr RICs? Are they under warranty? Perhaps they should be serviced. If they are RICs maybe is something bad in receivers and changing them to new ones could help.
You’re ignoring this member’s posts.