@zprime
I upped this very old thread, because it helped with my pfsense 22.05 plus system.
Sometimes i have been problems with jammed connection, normally i do reboot and all go again fine.
Now i started use IPv6, and i noticed very often jamming problems.
I noticed removing lan cable cause unstable state and it not go back with replacing lan cable.
After many hour googling, i found this thread and it helped.
When i put fixed 1000T fd state all my NICs, pfsense is solid again.
I hope some speaking why this very old bug still exist.
I have intel 4 port NUC