Name the songwriter from San Francisco who operates the Art of Ears Studio and who worked with the lead vocalist for the hip hop group Digital Underground?
Andy Ernst:  Artists he has worked with include: Green Day, AFI, Sway & King Tech, Rancid, Tiger Army, The Nerve Agents, Malo, Link 80, Screeching Weasel, Swingin' Utters, Screw 32, Good Riddance, Fury 66, Shock G and Money B.
i don't know