Has anyone else who uses a Becker AR-4201 radio experienced background noise only on 123.5 MHz?

I thought there was interference being generated in my geographic area or in my plane, but I’ve now heard noise on 123.5 in 3 different gliders using 3 different AR-4201s. A friend using a Dittel FSG71M experienced no noise at all last weekend for 3 hours when I was getting background noise, which is when I knew I had a problem.

I can raise the squelch to eliminate the noise on 123.5, but then all other frequencies have less sensitivity, so that’s not a solution.

-John, Q3