I have found ( as well as the aeroleds guys) that the wiring to all leds need to be shielded-all the way to the circuit breaker in some cases. Follow the installers manual. Definitely , shield the wire and ground the device with a separate ground from the power ground.
You could also try a lone star line filter on the intercom v+ line. I've used these as a last resort on a couple installs with success. They're not cheap.
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Jon Hadlich
AI Systems
(541) 815-7381