There was alot of experiments ongoing back in the 2008/2009 era... Most were not successful..
One Ham Radio RV NET guy (CAMPER PAUL) had some luck using the miniture circuit board small strip chip capacitors and solder then across the 1156 sockets of the LED fixture like shown below...
Others tried ferrite beads everywhere around the 12VDC leads etc...
maybe some success...
I tried the easy ferrite beads on my setup like radio shack had and may have decreased it some but still had the interference...
I used to pull up close to the rear trailers that the big trucks had the new LED LIGHTs on them and it would blank out my ham radio haha...
Its kinda like the garage door electronic... FCC says they are in spec and may interfere with things when they are operated... As long as they make their claim all is good...
I would have thought by now the manf would have dropped the BUCK BOAST chips for regulators... I'm sure they all know about the problem...
Getting elcheapo LEDs from ebay china was my answer to the problem haha
This reminds me I haven't heard from Camper Paul in a couple of years or more... Hope all is ok We were both Illinois Ham Radio guys from the mid 50s...
Roy Ken