sghound 0 Report post Posted December 6, 2007 I've been listening to the HA-01 for the past few days, and I notice there isn't any hiss or hum.... funny, dead silent background. ( Will double confirm that after a audiclean session tonight.... hope nothing's wrong with my ears.) i concur. absolutely dead silent with all my cans. could be an improved version i dunno. Share this post Link to post Share on other sites