I have a 2000 JCM 2000 DSL. I've read much about bias drift being a problem on some of the early ones due to a defective PCB main board. Are the replacement boards available commercially free of this defect? Is there a specific issue of board to get in order to be free of the problem? I don't have the issue presently on my amp but am considering buying a board to have as a backup.
Thanks for your question! Best thing to do would be to contact firstname.lastname@example.org who will be best placed to advise on this matter.