Bought a Denon Ceol N-11 for my son. Unfortunately, this is not recognized as ROON tested. Think that’s because Denon deposited the hardware name DENON CEOL. Unfortunately you cannot change this. At ROON this is called Denon CEOL N-10. Of course, the CREOL also works perfectly, but it’s a pity that it doesn’t appear under ROON Tested and takes over the icon from the CREOL.
Welcome to the Roon community, @Christian_Elbl.
If the 11 is comparable to the 10, try going to Device Settings > Devices Setup, and for audio device, does this give an option to identify the unit? If so, select the 10.
This is what I do with my 2Qute; selecting the Hugo.
Thank you for your support. Yes, 11 is comparable to 10. Unfortunately, nothing can be changed in the audio setup, that’s my problem. The CEOL is connected via Airplay2 and listed in ROON Other network devices.
Roon Tested and RAAT need to use a direct connection from your core, e.g., USB. How is it connecting? Also, please take a look at Settings > Audio. If it listed and enabled there?
so my contact to Denon Support Germany. Translate by Google:
our AVR’s, mini systems and amplifiers with HEOS built-in are all Roon tested. This means that you are recognized as a device by the Roon server and music can be played via Airplay protocol. This also applies to the N11DAB model.
What we don’t currently support is “Roon Ready”. Roon Ready uses a special audio protocol to transmit the music information over the network from the source to the player. At the moment we cannot estimate when this will be implemented.
Airplay is how Denons get Roon tested status and or via HDMI for AV receivers. If doesnt appear as Roon tested it doesnt mean it wont work it only means Roon has not had it in house to test and give it that status. Your model is not listed on Roons Denon Roon tested page but it should work the same as ones that do via Airplay.
Not true Martin as you well know. Roon tested is not limited to USB at all.
This means, for example. 
I clicked the link to the Denon Roon page. Out of four Denon devices clicked, each one took me to a 404 page at Denon! Are all the other Roon device pages as poorly maintained as the Denon one? A question for support.
No, the Roon page is fine, it is the links to some of the Denon products that are dodgy. Fourth AV amp along the top row for example:
Oh yeah that happens a lot I guess know ones monitoring if the page address is changing OEM side.