I must have missed this comment in first participating in this thread. I accidentally added the Acoustic Phone program to my Quattro’s and sure enough, every time I put on my Surface Headphones over my HA’s, I activated the phone program because of the headphone magnets. Usually when I went into the Smart 3D app on my smartphone, I could switch the program back to the program that I really wanted to use with my headphones but after awhile I decided that I really had no use for the Acoustic Phone program since none of our regular cordless phones have enough magnetic flux to activate the program and so I just got rid of the phone program.
I see people have commented on headphones activating landline phone programs in threads here at least as far back as 2011 - so it’s something to look out for if you need a phone program but also want to wear headphones over your HA’s. You’d think in a HA app, they’d offer a way to turn the Phone program on or off - so it’s there when you want it but off if you want to use headphones, etc.