Marantz 1060 - fix for clicks/pops when pressing power button

About a year ago I replaced six caps in my Marantz 1060. The caps were c703/c704 & c707-c710. I did this because they were visually damaged and I thought it might help fix the clicks/pops that came through the speakers when I turned on the power and pressed the speaker select button. After the new caps were put in there was a huge improvement - almost perfect. Since then the problem has returned after a year of not using it - and its worse than before. When the power button is pressed there is a huge low frequency thud and the speaker buttons create loud static. I was considering doing a full recap after reading about some restoration projects, but then I saw some posts saying their sound quality was altered for the worse after recapping. Right now the sound quality is perfect for me - it sounds amazing. But the problem is so bad I fear damage to my speakers. I'd love to hear some opinions and ideas for fixing this - is there a sure fix for this sort of problem? One other thing to add - I got a spark when attaching speaker wire with the unit powered on. Is that not suppossed to happen or is it just something that shouldn't be done? I welcome all ideas and opinions.

Have you cleaned all of the offending switches?

You should not be connecting and disconnecting speakers while the amp is powered up

The 1060 has capacitively coupled outputs so turn on thumps and speaker switch thumps are normal.
You can reduce the magnitude of the thumps by inserting a 1/4 inch stereo jack or even a 1/4 inch to 1/8 inch stereo adapter into the headphone jack. BTW, this also works for the 1030 amp and the 2230 receiver.

Tom

I've been told that bad coupling caps can cause this, is it true?

If you are talking about coupling capacitors that connect in series with the power amp output to block DC from getting to the speaker, then no.

Read about what causes the thump in cap coupled output amps here.

Tom