Rule 1!!! Switch pre amps on and off ONLY with your amps off. It does sound a little unusual for a solid state unit to diplay start up transients. Until my recent change to tubed pre amp I never really felt the need to observe this rule. Maybe another Pro-10 owner can shed further light?
"Pop" in pre-amp
I recently purchased a used B&K Pro-10 pre-amp on-line. Whenever I turn it on, there is a "pop" in the speakers. This also happens if I switch in or out of the direct bypass mode. Does anyone have any idea what it might be? Is there a quick fix? Or do I need to take it in to be serviced or repaired? Thanks.