[Jack Jarmush]

Hello good people, I use a Roland Street Cube amp for guitar and vox
on small gigs and busking, it serves me well except there is no line
out so i can't plug into the house sound board in the pub (where they
demand to plug into their system so they can control the volume and
spread the sound evenly throughout the pub with there speaker system).
I want to use the Street Cube as a monitor/amp. How can i unmute the
headphone out so i can use it as a line out and still hear the amp?
Any advise is greatly appreciated. JJ