MommaBear, If you put them is the sink and run hot water over them, they will be better than pasturized foods, etc. I have worn them clean and filthy dirty. The clean ones work much better but the dirty ones same me from a brain crash.

Your son can play Guitar Hero because he is directly connected to the sounds. There is a visual connection to the sound that makes it easier. I can tolerate loud tools because I am standing at the tool and watching it make the sound. My brain does not need to try to understand the source of the sound. Sound is often a cause for alarm or fight or flight. When we can remove the startle factor, the brain does much better.

If an understood sound has too much background noise like echoes and excessive reverb, it can over-stimulate the brain as it tries to make sense of it. I can hear echoes that very few others can hear. It I point out the echo, sometimes, others will be able to identify it faintly.

My neurologist, after looking at my qEEG/AEP/VEP wave forms, could tell my brain was trying to process every bit of the audio stimulation. He said, "You hear everything. How do you handle that?" My wife was sitting nearby and answered, "He doesn't. That's part of his problem."

MommaBear, If you keep your son's index finger nails cut short, they can make excellent ear plugs for those emergencies. Have him try sticking his fingers in his ears with his finger nails to the back. It does better than any ear plugs or ear muffs. I'll do this for sirens and such. If his nails are long and toward the front, the nails conduct some sound. He sounds like a smart and perceptive kid.

My best to you all.