From Amarok Wiki
Rio Karma
Beginning with Amarok 1.4.4, the Rio Karma is supported in Amarok via libkarma. This allows you to connect to a Rio Karma which has been mounted using the USB interface. To mount your karma, you will need to have installed OMFS support for your kernel. In short, you need (tested with Kernel 2.6.21 on Gentoo (stable+some unstable)):
- A new kernel supporting the Karma partition types (KARMA_PARTITION) and USB Mass Storage support for it (USB_STORAGE_KARMA=y)
- OMFS module: Download, build and install (make modules modules_install when booted with the right kernel). The linux-karma site has lots of information on what you need to install this as well as hosting the omfs package for download.
- libkarma installed with headers, and Amarok built against it (should appear after the ./configure step)
Once you've installed libkarma and mounted the Rio Karma (i.e. mount -t omfs /dev/sda2 /mnt/karma), simply add a new device in Amarok with the mountpoint of your karma (e.g. /mnt/karma) and you should be able to view tracks on the device and copy new tracks to the device.