HI FOLKS, I HAVE A ZETAGI BV 603 HOMEBASE LINEAR THAT TAKES 3 X EL519 VALVES INSIDE IT, ONLY PROBLEM IS WHEN I KEY UP IT BLOWS THE FUSE THAT IS LOCATED INSIDE THE LINEAR. HAS ANYBODY GOT ANY IDEAS AS TO WHAT COULD BE WRONG WITH IT & HOW I WIL BE ABLE TO FIX IT??? CHEERS,SHAUN. 