I noticed when I parked outside the place where I used to work, I would lose reception on the car radio on FM. Even strong stations were affected. There is a control panel (fire or burglar alarm, I don't recall) that I traced the interference to using a handheld spectrum analyzer. I presume a crappy SMPSU.
I didn't think of checking just how high up in frequency the crud went.
On the plus side, it prevented one of my colleagues, with dreadful taste in radio stations, from playing his ghetto blaster. Until he discovered he could stream music on his phone