Hello,
fresh X1C owner here. I have 11 years printing experience with Ultimaer & Cura, so there is a lot to discover.
After printing some standard things, today I started profiling my first filament (PLA: ColorFabb Regrind).
One strange thing I can’t get rid off: after the first layer, the exhaust fan at the back always turns on at 100% making a lot of noise. I looked into the filament settings → tab cooling, but there are only settings for the part fan and the aux fan, no setting for the exhaust / chamber fan.
This can certainly be controlled as well. Can someone point me to the right spot?
Excellent, thank you for the quick and concise feedback 
I like Orca Slicer more and more. I’m using it for the calibration Tools only at the moment, but probably there is no reason to stick with Bambu Studio.
One more question: I guess when I use the setting in Orca, I have to remove the start G-code, right?
I think the latest update changed that. I’m printing right now and the only fan at 100% is the Part fan in the extruder head. The AUX fan is 70% and the Chamber fan is 60%. I can’t hear the printer over my HEPA filter fan anyway. The update also has quite routine to run for axis motors. It should be Version: 01.07.01.00.
The firmware update doesn’t change the chamber fan speed - as @3DTech notes this is controlled by the Start G-code in the filament profile. Bambu has modified SOME of the default PLA profiles to set a lower fan speed, even if the bed temp is high, but not all of them. You would see this only on a Studio update.
Thanks for clearing that up. I’m new to all this and it just seemed like it happened after an update. I’ll pay more attention in the future. But, for sure the quite motor routine works. 
since the last firmware update the fans run at 100% for parts, aux, and chamber. I have to manually set them lower for every print.
Use generic PLA instead of silk PLA.
Had the same issue and support told me thats normal for “Silk”
