Repetitive "pop" in Mackie console

[gnomefather]

Hi everyone, I'm a long time reader, first time poster! I'm 21, got into diy when I built a 1/2watt tube guitar amp when I was 13. Since then I've built a few more guitar amps and some tube hifi stuff, but I'm still a noob when it comes to understanding how everything works. Definitely interested in several of the projects on here, as well as learning more about electronics.

I recently purchased a Mackie 32.8 console. It worked perfectly when I bought it. I just went through and cleaned all of the ribbon cables and jacks with Deoxit D5, and the faders with Deoxit FaderLube F5. Now when I turn the power on (with no cables attached) I get a constant repeating "pop" in the left channel. I plugged in headphones at a low volume and it's almost like someone is tapping a microphone... it appears in the right channel at a MUCH lower volume. Any ideas? I figure since it's repetitive it must be a power issue... I guess power's going somewhere it's not supposed to? Also the master fader doesn't affect the volume of the pop at all, but when I unplug the inner ribbon cable going from the Power Distribution Board to the Master Section Board the noise stops.

Thanks!!!!!!!!!

 

[JohnRoberts]

General troubleshooting advice is first isolate what output the noise is on. If on all outputs then PS is suspect. If isolated to only a few outputs work backwards to find the common source.

Go back and review everything you touched.

JR

 

[bernbrue]

Hi,
I had this problem as well. It turned out that one of the ribbon cables was plugged into a wrong connector. Some of them are identical. So pay attention.
Regards
Bernd

 

[gnomefather]

Cool, thank you both for your input!! I'll have a look tonight and see if I can deduce anything.