Dell PowerEdge C6320 USB keyboard input lag/slowdown in BIOS/System Setup

Hello!

We are running several Dell PowerEdge C6320s, and have issues with USB keyboard input in BIOS.

When using a USB keyboard in BIOS/System Setup (accessed using F2 key), the input will be "intermittent". It appears to alternate every few seconds between rejecting all keyboard input and working perfectly fine. It will accept input like arrow keys and return/escape just fine for a few seconds, then it stops, and then it works again, and so on.

We have some newer machines too, and on those this same keyboard works perfectly fine.

I tried looking around in the system settings, because I have seen some devices have a "legacy" USB setting which can cause behavior like this, but could not find anything like it. The only setting related to USB functionality I could find was whether it should use USB 2.0 or 3.0, it is set to 3.0 right now, and changing that setting had no effect.

Have any of you run into a similar issue? Any idea what I can do to resolve it?