Hi Bruce

If you download and run "fing" on your phone, you should be able to see all devices that are on your network. Check to see if the 218 and QNAP are on the same network. Do you have a laptop? Please let me know what operating system you run e.g. Windows and I can make some more suggestions. Please can you also describe how the different parts of your system are connected?

Thanks
Tom

Main: G61SL, 218, HD621, 2*7200SE, 7200HCSE, M6s, DSW, Apple TV 4K, NUC (Roon server)
Secondary: Wiim Pro, 3200, Audio Core 200
F80