Looks like H13SSL-NT/H13SSL-N is a bad choice for a quiet build: the board does NOT like low RPM fans - it panics when a fan is below a (high) threshold and compensates by blasting them full force:
https://www.reddit.com/r/supermicro/comments/1fhr9o7/x13saef_fan_ramping_up_and_down/
“Only jet engines need to apply”