Hoping someone knows how to fix an issue with Bose A20. My A20's are great, but lately, in the past 5 months now, I am having some issues. When I start the airplane everything works good, then after a while when I talk, the sound that the mic picks up gets very low and muffled and sometimes just stops picking up sound. But it doesnt just happen immediately, its a slow process, almost like if the batteries were getting low. After my flight, I can go a few hours, start up again and the same thing happens. But then some flights, I don't have any issues. Its gotten so bad that Ive had to switch out with my david clarke headset because nobody can hear me. I can hear other people and the radio just fine, its only the sound that is picked up from the mic. I have changed the batteries several times and as a flight instructor I am in several plane throughout the day and it happens with all of them. If someone else has had this issue, what did you do to fix it? Ive tried contacting Bose but cannot seem to talk to anyone and for the cost of their repair, I can just order a new cord and mic but not sure if that will fix my issue. Any help would be greatly appriciated.