Hey @PluggedIn,
Volumio is not a customised Raspberry Pi OS. It is a purpose-built system with a fundamentally different disk architecture. This is why you see things in Windows that look strange.
Your 128GB card has three partitions on an MBR (msdos) partition table:
Partition 1 (boot) - FAT32, 384MB. Contains the kernel, device tree files, and boot configuration (config.txt, cmdline.txt, userconfig.txt). This is the only partition Windows can read natively because it is FAT32. It is NOT “the Volumio OS” - it is just the bootloader stage.
Partition 2 (imgpart) - ext4, approximately 4.2GB. This is the 3.99GB partition you see in Windows Disk Management. It holds the Volumio system image as a compressed squashfs file (volumio_current.sqsh). Think of squashfs as a read-only snapshot of the entire operating system packed into a single file. Windows cannot mount this partition because it is ext4.
Partition 3 (volumio_data) - ext4, everything else. On first boot, Volumio automatically resizes this partition to fill the remaining space on the card. On your 128GB card, this is the 113.40GB partition you see in Windows Disk Management. Windows cannot mount it because it is ext4. Do NOT delete this volume - it is where all your persistent data lives.
How these three work together at boot:
- The Pi loads the kernel from partition 1 (FAT32 boot)
- The kernel mounts partition 2 and finds the squashfs image file
- The squashfs image is mounted read-only as the base operating system
- An overlayfs layer is created on top, using partition 3 for all writes
OverlayFS is the key concept. It merges two layers into one view: the read-only squashfs (lower layer) and a read-write directory on partition 3 (upper layer). When the system reads a file, it looks in the upper layer first. If not found, it falls through to the squashfs. When the system writes a file, it goes to the upper layer only. The squashfs is never modified.
This architecture is what makes OTA updates possible. A new update replaces the squashfs file. The upper layer preserves your settings, plugins, and data across updates. It also reduces SD card wear because the base OS is never written to.
There is no Raspberry Pi OS GUI underneath. No desktop. No file manager. Volumio is headless by design. The HDMI output you see on your Onkyo is Volumio’s own display interface, not a Linux desktop.
Now - the part that actually answers your question:
Volumio already exposes your internal storage as a network share. The path /data/INTERNAL on partition 3 is shared via Samba (SMB) automatically.
From Windows:
- Open File Explorer
- In the address bar type: \\volumio (or \\<your_volumio_IP>)
- You will see a share called “Internal Storage”
- Copy your music files there
From macOS:
- Finder - Go - Connect to Server
- Enter: smb://volumio.local (or smb://<your_volumio_IP>)
- You will see “Internal Storage”
Once files are there, go to Volumio’s UI - Settings - Sources - and rescan your music library. The internal storage content will appear under “Music Library” in Browse.
You do not need to remove the card. You do not need to create any share manually. You do not need SSH or any Linux knowledge. Just use the existing network share.
As @SimonE correctly pointed out - /data/INTERNAL is where your music goes. The network share is just the convenient way to get it there from another computer.
Kind Regards,