DDJ 400 freeze & headphone buzzing issue.

I just bought a DDJ 400 and when I try it I have a buzzing in my headphones I turn off the headphone knob and didn’t work I restart my dj software and work normally, this problem happens no Virtual DJ and Rekordbox, later when I was performing at night the controller freeze I unplug the DDJ 400 and restart the Virtual DJ and work normally and never did it again, yesterday the problem same problem happened and I did the same. Please help me with this two problems! I have a XDJ RX2 and I dont have any problem