Likely something related to music doesn't have the correct ownership and/or access rights, for example the music files themselves?
Being able to use sudo without password is not significant by the way, the system does not switch to a different user to resolve access problems by itself. (Which is a good thing imho, making sure everything has the right owner, group, and access rights is a far better solution.)
What permissions should I use for the files? I noticed that a separate config file and content-download folder are placed into the user's home directory - so surely the user should own them?