I don’t know if this is a universal thing, but certainly BBC Radio 1 does it all the time: when interviewing somebody by phone, they play an intrusive hi-hat-heavy CHIKK-chikk-chikk-chikk-CHIKK-chikk-chikk-chikk instrumental track for the whole duration of the interview. They do the same with listener call-ins.
If you’re trying to listen somewhere with background noise, like on a car radio, all you can hear is the high-frequency music and it totally drowns out the voice you’re trying to listen to.
What is the purpose of this annoying habit? I assume there must be a reason, and it’s not just to annoy people?