Here are the LEDs I used.
https://www.ebay.com/itm/10pcs-G4-GU...ye-l:rk:8:pf:0
When the trailer is plugged in, I get audio feedback over the speakers of the radio when its on (unsure of television, I have not tried it). When on battery power, its dead quiet.
Something with the voltage regulation circuitry in the lamp sends feedback to the converter I guess. I saw another thread recently with the same noise issue with these lamps. I have not tried any new LEDs yet.