Verify the username and password (connect directly from your Mac to the NAS to test). Make sure the account has rights to the music share. And make sure the path is correct…
So we can better assist you, please describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
If you open Finder on your MacBook and paste smb://192.168.0.13/DiskStation/music, are you able to access the NAS?
We have some information about connecting to your NAS in this KB article that I definitely recommend checking out!