@krellboy did you first try with any other pla? I also had the same results with green Bambu basic pla using the default bambu filament profile as seen in the pic. It shows up within the first few layers, so no need to print the whole thing. In fact I would be right next to the printer the whole time to listen for chatter as the ripples began to compound and stop the print there.
I was thinking about the nozzle being a culprit too! That’s why I did a cold pull even though I only had 20ish hours of printing on it with ABS and PETG before going to PLA, but no difference. And if AMS is the issue, then I’d most likely return the printer since that’s one of the selling points for me, so I was trying to find alternate solutions. But for completeness I’ll actually try direct feed too soon.
I did run another test. I wanted to see if electrical noise/firmware bugs from the part cooling fan being on could be affecting things so I taped up the ducts while running the fan, and nope the ripples didn’t show when taped up.