SanDisk Clip Jam volume adjustment

I recently bought the SanDisk Clip Jam after having used my older SanDisk for many years. I like to go sleaping listening to music, the volume set very low.
Regretfully the Lowest possible volume setting on the Clip Jam is still to loud for me. I’m not able to adjust the volume in small steps.
In the system setting I’ve set the volume to normal, high being the only other possibilty. My old SanDisk allowed me to control the volume in a much finer way.

Anyone knows how to change this?