I am away from home at the moment. Will check the fuses again when come home. In fact at the very first time connected to power, all tubes lit up but no sound at all, I did find a AC 3A fuse blown on left channel but not sure if it already blown before arriving to my door or after I connected to power. I replaced a new fuse, thus 3 blue LED on face plate lit up, Tubes all lit up but NOT the tube red bias indicator. Wiring are connected properly. Still not hearing nothing. I think adjusting bias level has nothing to do with no sound issue. Incorrectly set the bias level can affect the sound quality. I have the menu, but little confusing to read. At one time I do hear a low level distortion sound while adjusting the bias level, until the red LEDs turned on and went off. from there I have not checked for blown fuses. Gotta go out on business trip until next Wednesday. I sure will post what I might find out. Thank you, guys. Happy holiday!