Unfortunately it's not the power supply...Thanks anyway. Any other suggestion? Mozza Recently Mozza wrote: > I'm trying out a VX pocket souncard with logic Audio gold and I want to see > if anybody has the same problems I have. ....... > As soon as I plug in the card into the Powerbook a strange (high pitched) > low noise comes out continuosly from the built in outs of the PB. Some power supplies are bad. try to work only with batteries. If the noise problem has disappeared, get a custom made power supply. -- Klaus Lotz e-mail: klo@... http://www.musicshop.de