Problem with Intel 82566DM Gigabit Network Adapter

[Skunky]

Hi. I'm having a problem with an Intel 82566DM network card. It's integrated into the motherboard on an HP Compaq DC7700 Convertible Minitower. I have OPNSense 20.7 installed, and other than this on NIC, it's working great.

I've noticed that the NIC connects at gigabit speeds when the computer is first turned on, then, when OPNSense starts, the NIC drops down to 100 TX. If I force the NIC to gigabit speeds, it's stops working all together.

Is there a way to fix this? Is there a problem with the driver on a BSD level?