sound issues

this is weird, it worked fine for five minutes now if i plug in my headphones the sound goes away, then i close the file and restart it with the headphones plugged in and i get sound thru the phones once i unplug them the sound goes away again. is there a button i am missing? it works then if i plug or unplug anything from the out put jack it quits. this only happens with the cubase program. please help.

This is wierd.

Cubase doesn’t know, when are your headphines plugged in, and when are not.

What is your sound card?

Are you using any DEMO (Trial) plug-in?

Disabling the control room might help?