My MF10s do make a slight clicking/whirring noise when idling, which is only really noticeable if it is dead quiet in the room and you get close up to the speaker, and is no worse than any other active speaker I’ve had. In normal use, it’s not noticeable at all. For example, my CLRs (I’ve had 4 in total over the years) all produced a VERY noticeable hiss when idling, and that was definitely louder than the idling noise of the MF10s and my Presonus studio monitors emit a slight hum, again more noticeable than the noise from the MF10. I’ve never considered it an issue, as it doesn’t increase with volume and they work great - it’s just a faint noise when my room is dead quiet. But if you’re finding your speaker making some noise that is abnormally loud when idling, then its definitely worth getting in touch with G66 and I’m sure they’ll help.