Easyvibe chorus/vibrato switch pops....why?

[BDuguay]

I get a very loud pop when activating this switch. I've tried 3 other switches and it's still there. I never had this problem with the first one I built. I scoured the archives for an answer but to no avail.
Does anyone have any suggestions?
Thanks.
B.

[R.G.]

Popping is *always* caused ultimately by instantly changing a DC level when the switch moves.

Is there a DC level across the switch when it is open?

[BDuguay]

Thanks for responding R.G. Incidently, it's the layout from your site that I'm using. I'm not sure what you mean by your question but, once it is explained to me, it will not need to be explained again. I'm like a sponge that way. Would you mind elaborating a little please? Is there a way to measure for a DC level?
Thanks,
B.

[lightningfingers]

Take a DMM. Set it for DC, connect the -ve probe to ground and measure the  pins of the switch for DC...

[BDuguay]

I kinda figured that's what was reffered to. Now, if I find DC voltage, and it looks like I will, then what? Is it a matter of checking out the circuit to see if there is some caps in backwards or maybe a jumped trace? I think I'm getting the idea now of what might be causing this.
Thanks again.
B.

[R.G.]

I kinda figured that's what was reffered to. Now, if I find DC voltage, and it looks like I will, then what? Is it a matter of checking out the circuit to see if there is some caps in backwards or maybe a jumped trace? I think I'm getting the idea now of what might be causing this.

You're dead on. Fast learner!

[BDuguay]

K.
I measured the three leads that go to the popping switch and, to my surprise, they all had DC present. The wire that goes to the middle lug, however, was reading twice the DC voltage as the other 2 wires. I then quickly tested another Easyvibe board I have ready to box up, knowing that its switch doesn't pop, and discovered equal DC voltage on all three leads. So, I deduced that popping will occur when the DC levels are not equal and won't when they are. Is that about right?
I wasn't able to determine why the offending Easyvibe was getting extra voltage on the middle wire but, I was able to solve the problem by re-flowing a bad solder joint on one of the opamps.
I would like to point out that, while I have made a number of Easyvibes, I am not, and will not,  even entertain the thought of mass producing these for profit. It's just that when I shop for components for a pedal project, I seem to end up buying enough to make a half dozen or so. Blame it on my OCD.
Thanks again everyone.
B.

[R.G.]

Good job! Contrary to what you said, you WERE able to find out why it had excess voltage. A change that restores normal function is the definitive test.