2015 EX-L, USA, with shark fin antenna and LED headlight bulbs (not retrofit, just on original reflector housing). Mentioning this so you know what changes I've done in case any of those might be the culprit.

I just noticed today that when I have the headlights off, the radio signal is strong. If I'm stationary (or moving but tested not moving for control purposes), and then switch to turn on the headlights, you can literally hear some static and the quality of the FM radio signal worsens. I turn off the headlights and I immediately hear the signal back to strong and clear.

Anyone noticed this?

 

LED headlight drivers are emitting radio interference from being un-shielded Chinese pieces of crap. You aren't the only person to have this problem.

Replace the LED's with quality halogen bulbs, like the car was designed for, and I guarantee that this problem will go away.

Side note, if you live in the United States, headlights are considered a safety component of the car. If you modify a safety feature and have a crash at night, be prepared to have insurance not pay out if anyone involved claims to be blinded by your illegally modified vehicle. Yes, this is an illegal modification. Just something to think about.