Battery inverter humming when everything off

[turkii]

First time camping in our Jayco 32BHDS this weekend and noticed that the battery inverter hums and buzzes when the battery is fully charged and all the DC lights and other DC loads are off. If I turn on any of the DC lights this buzz immediately stops, but obviously don't think it's practical to leave a light on 24/7. Has anyone experienced this issue, and any good tricks to deal with it - or am I missing something?

[fmichaels]

Check the inverter fan. In my old pop up, the inverter was buzzing and it turned out to be the fan hitting inside the casing. Not sure if that would explain the sound stopping after lights are turneed on, but I remember this similar situation and the fan was the problem.

[LiftedAWDAstro]

My daughters 22FB does this. I think she just leaves a light on. My older ears don't hear it unless I get real close to the converter. I have checked all the wiring connections and voltages and they were all good.