Hi! New to the site, really just found AK 2 days ago. Been reading a lot about my little amp over the last couple of days. So, let's get to this. My dad bought the IA in1970, gave it to me in '86 and I've used it most of the time since. I took it out of the closet today and hooked it up(My Nak730 just decided to quit). Still sounds great but the right channel seems to have dropped off slightly on the high end. I don't get any hiss until about halfway up the dial. Power seems equal left to right. Switches need cleaning. In all the reading I've done here the past days I learned quite a bit. Now the question. Since it seems to be operating well enough, should I consider the cap and transistor exchange? Or should I wait for the performance to drop off?