I had the same noise when using multi voltage LEDs (10-30V) for the tricolour and and anchorlight at masthead. The distance from the masthead antenna was about one foot may be some inches less.
That happend when using Multivoltage LED bulbs in the Tricolor and also after changing to the NAVILED pro from Hella which design convinced to buy.
With the AIS I had no problems as the antenna for the AIS was about 15 feet above deck
level and so about 50 feet away from the tricolor and anchor light. In my opinion and experience high enough to receive AIS Signals from ships more than 30 Miles away or even Nav aids up to several hundred Miles away (eg. Cap Finisterre when leaving the Azores).
If in need to use the VHF I changed from the masthead to the decklights, but that was so seldom necessary so I was not looking for a change.
When I changed the first time from normal bulbs to LED that was done with night owl LEDs from Fiji
11 years ago. But the withe LED in the tricolour changed the colour of the green segment to near blue. It failed soon and was replaced with no hassle and I used the powerful LED as an near deck anchor Light after. Reason: often the anchorages
where crowded at night by dinghies and fishermen so I found a powerful light not high above the water