For zeveck, does it make the noise when you use the jog mode on the controller? That might help you isolate it to an individual module.
There’s an old post with a video. Is your sound similar? It’s kind of hard to hear, but in the video I hear some kind of humming with travel on the ±Y axis. That post says a little WD-40 cleared up the noise, although they never posted a followup.
It does seem like the original linear modules are going to need some lubricant at some point. In my opinion, WD-40 isn’t the right choice for that. I’d go with the Snapmaker recommendations.