1986 M20J. I keep losing radio contact on trips. It seems to be getting worse. Garmin 650xi. Installed about a year ago. When I am close by a center or tower, I hear fine. Sometimes a little scratchy. My comm 2, old king works great. Have had the plane in the shop. They checked everything and it all checked out. They did lower the squelch break % and it helped, but it is not fixed. Long cross countries with imc, it sure is nice to be able to talk to someone. Any ideas? Shop wants to put new antenna on and re bond. Thank you.