Maybe the seals then.
with your reply, and now that I'm thinking about this more, I think I remember buying some of that seal conditioner when I first bought the MH.
this stuff I believe
https://www.amazon.com/Camco-41105-S...al+conditioner
and it helped. the noise I was having.
it sprays out like a foam, but it's like a light silicone lube
I have since learned that most folks consider this stuff unnecessary & I certainly haven't found that i need to use it regularly.
But I do believe I was wondering about some similar noises when I first got ours
and maybe doing this lubrication (seals &/or track nibs)will help to reduce it while things get worked in a bit....
worth a shot I guess.