your problem is the fact that your directory name consists of two words.
you may to use the “” in front of the space (e.g. iTunes\ Music) but this may not always work, depending on the “shell-environment” the command is running in. (in linux or unix O.S.s every command runs in its own environment, i.e. sh, ksh, csh bash. Some will and some won’t work with escaping the space-character).
a “quick and dirty” way is to alter the name of the directory on your NAS and replace the " " to a “" as an example. I did the same. The "” makes the name to one word.