...are giving me the biggest headache of my life

no matter which fan ( 3 pin - they are more inconsistent, its like they dont respond to manual settings eg 25%, 4 pin - are little bit stable ) i plug into SYS_FAN, CHA_FAN, or any other ( tried them all ) i just cant get a stable/consistent/reliable control over the fans.
One day they work as intended eg 20%, smart control, 90%, ... - it doesnt matter because the next day or some random day in the future, suddenly one or all fans go to 100%.
I tried:
- replacing CMOS battery ( two times ), i thought that this was an issue, but when i go into the BIOS all the settings are still there, its like the fan doesnt want to cooperate; 3 pin fans in particular, one time they are set to 20% and all is good, next day it responds only to 0%, then it doesnt work, but if i put it on eg 10%, 50%, 60% it will ignore and ramp up to full speed of 100%...
- all fan headers and all possible combinations/variations
- replacing the fans ( i was using some old CoolerMaster - 3 pin fans, replaced them with brand new BeQuiet Shadow Wings 2 - 3 pin fans )
- same as when PC wont boot/start ( remove everything, plug one stick of RAM at the time, etc... ), i tried plugin in one fan at the time, and then changing the settings in the BIOS per fan; with one fan plugged in and set to 20% all is good; as soon as i add one more fan and change the settings in the BIOS for that fan, one of them goes to 100% and the other is working at set speed, at random motherboard choosing...
I went the 3 pin route because i dont need the smart control over the fans, i just want them to be a bit quieter
Any help what to try next is highly appreciated

( pls dont tell me to buy more fans

)
Cheers!
system: X299 FTWK, i7 9800X, EVGA 3060 12GB, 64GB 2666Mhz RAM, Asus dual 10GB nic, Seasonic Focus Platinum 650, FANS: front 200mm, back 120mm, side 120mm, CPU cooler 2x120mm, bunch of HDD/SSDs, BIOS 1.28