I have a 69 Gibson Duo Medalist that is a two channel all tube amp with channel 1 having Reverb and Trem. The tremolo sounds great but it makes an faint audible tick when it oscillates when the speed is between 0 thru 7 ish. When you play it can not be heard. It is pretty faint. I have changed tubes and no change. There is a light that also turns on and off with the oscillation of the tremolo. Also, when I turn off that circuit via the footswitch the sound stops. First, is this typical of amps with a tremolo circuit? Is this a symptom of it being vintage perhaps? Is there anything that I can do to eliminate it? Might a recap of that circuit be necessary or something like that? If anyone had any insight I would appreciate it if you could help me out. The amp sounds killer and the tremolo sounds great but when not playing you hear a faint tick tick tick as the light flashes on and off. Thanks in advance for the help.