Repair Shop in Southern California

Is the click coming from the speakers or the amp itself?

" The click is from amp and only noticeable when not playing music. I did some web research and most ppl say it is related to protection circuit been activated.  They are old amps but I just love them."

Before you send it out for repair, you may want to go over your system. Given the age of the component in question, I would check all the cables, including the power cord, for any type of corrosion at all the contact points, and for damage.