Just built my first bike and I have the chain rumbling like this (please ignore the crazy freehub noise popping up here and there)
https://youtube.com/shorts/Ib4CJ3dFoycDerailleur seems to be set propely, moves up and down all the range with no problem and the chain isn't touching the adjacent cogs.
Front derailleur should be fine too, this happens mostly on the bigger chainring in both trim positions.
What could it be?
A bent cage?
Twisted hanger?
Cassette working badly with the chain?
Parts are:
Groupset Shimano 105 R7000
Chain Decathlon (KMC) X11
Cassette Goldix SL cnc