Big hum when engaging EMG PA2 via true bypass DPDT switch...

[wollyroger]

Hi, 

I'm hoping someone can help...

After finishing my guitar project I was slightly disappointed that my 'off' setting of the EMG PA2 switch wasn't true bypass, meaning the guitar would always be active (so dead battery equals dead guitar - not what i wanted!). I therefore added another push/pull pot to try and make a true bypass circuit, but have ran into an issue - when I engage the PA2 I get a massive hum. Please see video: 

drive.google.com/open?id=11EXCUsnVbgwQmD1XWzF0Bcoqurv7X5NH&usp=drive_fs

Full wiring diagram is here (haven't shown the battery connections, but they go to the PA2 and jack socket):




Should this work? If so, why the mad hum?

Any help would be much appreciated...! 

Thanks :-)
Rog

[wollyroger]

Forgot to mention, humbucker is a dimarzio...

[wollyroger]

Managed go get a reply from EMG on this - apparently my wiring caused a feedback loop, hence the hum.