How do i get the telephone signal off my radio it interferes on my music my CDs with a buzzing noise

Hello, I'm assuming this is not a "Bluetooth" situation, and no added accessories are present. I'm baffled as to how there could be interference. These devices don't share any common frequencies that I can imagine. There must be aftermarket components involved? I'd recommend seeking guidance at a local shop near you where hands on testing is possible. Too hard to know without first hand inspection.