burp-ui exists after launch

Hello,

I have another strange issue on my setup.

When i launch

burp-ui -c /etc/burp/burpui.cfg

Nothing happens and i get my shell back (doesn't get into background neither, checked with ps aux) When i launch

burp-ui -c /etc/burp/burpui.cfg -v

The program stays open with log files and i can connect to the UI interface on port 5000.

This didn't happen a day ago, altough i did not make any particular system changes. /var/log/messages doesn't get any additionnal info (running Centos 7.0).

Any clue ? Regards, Ozy.