change name of player

Hi
I want to use two raspi’s with hifiberry in two different rooms. Each if them is running alone and I can use them from my iPhone with the MoBD app. But I would like to run both at the same time with different playlists. I tried to change the name of one player in the web interface, but there was an error and i had to completely reformat and reload the mc card. Since then I have a share named volumio and one named (none).
How can I change the name via SSH or web?
System: OSX 10.10.5

Did you have a look at the config files?

/etc/mpd.conf

/boot/config.txt

Though I never had any problems renaming from the web interface.