chamaeleon

I don’t use Calibre for this (but I do for epub and pdf ebooks). I use Plex and use Plexamp for my music collection. For audio books I used to have Chronicle Audiobook Player installed (which is open source, but not actively maintained) but am now trying out Listen Audiobook Player (which is not open source as a heads up). Both of those allow me to download books wherever I am.

If you have no interest in running a Plex server neither of them are suitable for you, but I just wanted to mention this solution in case you’re not dead set on using Calibre. Plex has a cost factor which may come into play (an obvious non starter for some). I have had Plex Pass for a long time so it was natural for me to use it, but might not be for you.

Since I can’t see any other reference to it, I want to mention I’m using openmediavault and export smb mounts for my windows computers and NFS for Linux. It is running in a VM in proxmox. Works well enough for me. It is my in house backup destination, and my Plex media files storage (plex is running in a container on the same proxmox host).

Like most and probably every other mentioned solution, accessing the nas/shared storage is not more difficult than just opening windows explorer on windows and selecting the network location, etc. I’m sure it is easy on Mac as well, but I don’t use apple products myself.

Plexamp is my primary music playback in the car commute if I’m not listening to an audio book. Love it.

Proxmox with a bunch of small dedicated lxc containers (running small Ubuntu lxcs mostly). It works for me anyway, though I don’t use any of the rr programs. My Plex lxc gets its Media files from an openmediavault NFS mount (Running in a VM instead of lxc), and I use smb file sharing for my windows desktop to access the same files. Your mileage may vary, what works for me night not be for someone else.