Harry this issue is resolved. I noticed the image downloaded was for Pi 3 ergo the ‘unsupported board’ error code. Downloading the uncompressed file worked. I just checked the XZ link for Pi 4 on your website and indeed I get a new Pi 4 file so I suppose I clicked the wrong link. The only oddity is in the ‘Devices’ tab, after renaming the Hostname ‘LivingRoom’ for one and ‘Den’ for the other: When the LivingRoom unit is active the table has 2 entries, “LivingRoom” and “Den”. When “Den” is active there are 3 entries, “Den [ME]”, “Den-2” and “LivingRoom”. The router still sees “ropieee-1” and “ropieee-2”. Roon retains the old names: “RoPieee Den” and “Ropieee LR”. Everything works fine so far, so no problem with this.