Somehow forgot to include the link to the walkthrough. I do think it’s worth a read because it illustrates the file hierarchy I’m recommending:
Close. When you create a Docker container, you typically need to provide mappings from the host system into the container. A good pattern for this is to create a top-level folder on your NAS called Docker or docker and then create a subfolder for each container you create. Roon may be your first container but you should look ahead and assume that you may want others in the future.
So…create a share/folder/whatever on TrueNAS called “Docker”. Then create a folder in there called “Roon” and, within that, create app, data, backup folders. Map those into the Roon container using the “volume:” section of your YAML file.
I’m not recommending that you put Music in there because you already have a Music folder. Just map that one in as you’ve been doing, but verify that the path is correct.
The walkthrough I created a few years ago explains how to do this in the Synology UI and, even though that’s not what you’re using, it shows the file hiearchy that I recommend you create.