I wear 2 Phonak Nadia B aids. Phonak and other brands have automatic switching programs where the hearing aid itself analyzes the environmental “noise” and adjusts accordingly. I personally don’t like the automatic adjustments and had mine disabled . I manually switch programs depending on where I am. The only automatic program I have right now (which I think is built into Phonak) is that the aid will go mute if the noise level is too loud. I ‘ve had this happen at inopportune moments. This sounds like what is happening to your son and can most definitely be adjusted by your audiologist. I prefer to analyze my own environment and switch to whatever program I choose. That being said, I would also have his ears checked out by an ENT if you have not already done so.