AMS 2 Pro: PETG won't load on slots 2 & 3, works fine on 1 & 4
P2S + AMS 2 Pro here. Some of my PETG spools (all Bambu, all with RFID read correctly) refuse to load on the middle slots. During the load sequence where it feeds past the hub and retracts to measure how much is left, the filament retracts too far and just pops out of the feeder. No error, nothing on screen. Move the same spool to slot 1 or 4 and it loads first try.
Here's what I tried today:
* **PETG Black** (new, full spool): failed on slot 2 (multiple attempts), failed on slot 3 (3 attempts), worked on slot 4 first try * **PETG Transparent** (about half used): worked on slot 2 on 2nd attempt. This one gave me the same issue before on slot 3 and I moved it to 4 as a workaround * **PETG Grey**: works on all slots, every time, no issues
Grey and transparent were dried together in the AMS before this. Black was on the external spool holder the whole time, never went through a drying cycle. So it's not a drying/temperature thing. I also tried leaving the lid open for a few minutes between attempts to cool down the chamber — didn't help.
Tried both original Bambu spool holders and custom printed ones, same behavior.
The black spool is the worst - it literally ONLY works on slot 1 or 4. Grey works everywhere. Transparent is somewhere in between.
Has anyone else run into this? Is there a fix or is this just how AMS 2 Pro behaves?
I have a video of it spitting the black one out, but unless it's actually relevant, I won't bother with it.
Thank you