Indeed it’s quite rare to hear of a More user complaining about hearing a slight hiss, which is usually the floor noise that the user hears. That’s because usually the floor noise phenomena is only pronounced when the HAs are set to beam forming mode. See this thread in the forum that discusses it in more details.
If indeed it is what you hear, then your audi just needs to take you off that Full Directional setting and you shouldn’t hear it anymore. But I realize that it’s already water under the bridge for @texaco24.9 since he went with the Phonak anyway. But his HCP could have easily fixed this if it were communicated to the HCP and the HCP were a competent one to recognize exactly what the problem was and knew how to fix it.