Is there any sort of EMC filtering in the line to the lights ? - Note that the reference levels of what is permitted  when CE marking,  in terms of  how much high frequency crap you can inject into the mains were set based on one unit interfering with victim equipment in a neighbouring property. (mil spec standards are in most cases at least 20dB tighter, but that would make stuff more expensive)

It does mean that you can not guarantee that co-siting of interference source and victim will always work, nor does it consider the possibility of multiple potential interference sources in parallel.

You have both, I think.

Waving a medium wave or long wave (AM) radio near the wiring (any part of it not in earthed armour or steel conduit)when the LEDS are on and seeing if there are noise like radio signals that stop when the lights are switched off is a quick way of deciding if that is a possibility.

But do check the voltage drops first, not least because it is easier.

Mike.

Is there any sort of EMC filtering in the line to the lights ? - Note that the reference levels of what is permitted  when CE marking,  in terms of  how much high frequency crap you can inject into the mains were set based on one unit interfering with victim equipment in a neighbouring property. (mil spec standards are in most cases at least 20dB tighter, but that would make stuff more expensive)

It does mean that you can not guarantee that co-siting of interference source and victim will always work, nor does it consider the possibility of multiple potential interference sources in parallel.

You have both, I think.

Waving a medium wave or long wave (AM) radio near the wiring (any part of it not in earthed armour or steel conduit)when the LEDS are on and seeing if there are noise like radio signals that stop when the lights are switched off is a quick way of deciding if that is a possibility.

But do check the voltage drops first, not least because it is easier.

Mike.