UR22 vs UR22 mkii noise floor

I made a recording with my UR22 with no inputs connected and volume knobs set to zero. Here is a frequency spectrum plot of the recording:

http://i.imgur.com/v6T4toZ.png

This is a bit too loud for my intended use of the UR22. I’m considering buying the UR22 mkii instead because I read somewhere it has a lower noise floor. Is this true and how much improvement can I expect?