Ludwig -- I now have the 818 update file but have trouble installing it. The Flash Uploader doesn't see the 818. I have made sure the USB cable is plugged into the maintenance port, disconnected everything else from the 818 (except the DSP8ks), power-cycled everything. No luck. Windows 10 hypothesizes that the 818 has an old USB adapter that can't handle USB 3, which would be strange because the music input is over USB3, from the NUC. In fact the NUC has only USB 3 -- I'll try tonight with an older machine.

Does anybody know anything about this?

Strange, I did update the 818 six months ago, don't remember any problems...

Music room: 818v3, DSP8000SE, Roon/Intel NUC, microRendu/LPS-1 into Geek Pulse Xfi into Audeze LCD-3
HT: G61R, HD621, MS600, Oppo, Avantgarde Solo
Library: MS600, Bel Canto, Mark & Daniel
Other: SonicOrbiter, GeekOut, Audeze EL-8