I seem to be having a common problem. I’ve got an external hdd on a mac on my network that has my shared music library on it. I can’t seem to get volumio to mount the share. I have tried a variety of things from the forums and still nothing seems to work. Any suggestions? Also, I’m going to be putting together a freeNAS build. Anyone have any success getting volumio to mount a share from freeNAS?
Erik
I too am having the same issue. The documentation has no mention of how to access SMB shares and the forum seems useless. I have been searching here for the last 30 minutes and have yet to find an answer. I am trying Volumio because I cannot get PcP to play DSD. I guess I need to move on to yet another Pi player. 
Go to the gear icon -> “My Music” -> scroll down to “Network Drives” and hit the “Add new drive”, then click the “advanced options” box. Insert the NAS IP address in the relevant box. In the box below called “Path” set the path on the NAS drive to your music relative to root, Volumio won’t find it without that. The next box below enables you to select the fileshare type which in this case is cifs. My NAS drive is a Vortexbox which by default accepts guest logins so the username, password and options are left blank.
Samba permissions are a bear, at a guess that’s where the problem will be found.