Alright, fair enough. I read on their website (Thesycon - USB Software Development) that it doesn't measure correctly in Windows 8/8.1. I just used their own compatibility list, for which operating systems DPC Latency Checker works on. Windows 10 isn't listed - this is where I started questioning stuff. Maybe I jumped to conclusions way to early about whether it measures correctly in Windows 10 or not, I haven't found any information about that - but I do know that LatencyMon works so that's why I pointed that out.
But I believe you! I'm not judging or anything... I tried to point out that I wasn't sure about the compatibility/correct measures with DPC Latency Checker in WIndows 10, since it doesn't work for Windows 8 or 8.1. I use a DAW also, but probably "newbie stuff" compared to what you're using. I know that high DPC latency is terrible when working with audio.
About the release notes for this driver set... It says "Intel(R) Network Connections Software Version 20.4 Release Notes" - but it should be 20.4.1 (?), so I'm not sure if there is a miss somewhere. But the driver clearly works for me. Further down in the release notes it says:
Audio or video distortion when LAN cable is connected or disconnected
---------------------------------------------------------------------
Momentary audio distortion or video playback issues may occur when you
connect or disconnect a LAN cable to the onboard Ethernet port.
Intel(R) 82577 and 82578 based network connections are affected by this
issue.
I have a Intel 82579v NIC, and now it works great. My NIC isn't listed in the release notes, and it works. 19.1 was the last version before the 20.4.1 driver that worked for me.
Sorry that the driver didn't work for you!
Peace!