Can I choose audio device in some way? I have an external usb device well configured for Skype.
Can I use it in GMusicBrowser as well?


Thank's for suggestions

I don't much about it, but I think you can either configure it globally for your system, so that everything will use it by default. Or you can use advanced options in gmusicbrowser's audio tab to configure gmb to use it, I'm afraid I can't really help you to find what option is needed. If you use alsa you can look at alsa documentation. same for pulseaudio, but there is also a gui for pulseaudio (pavucontrol) where you can change the output of any stream, the setting might be remembered but I'm not sure.