Zero Loss Loop in Twainwreck Express clone?

[freakshow__]

I'm trying to intall the ZL Loop in a Trainwreck Express clone I made for a friend. I have installed it between the 3rd gain stage and PI, but there is a problem. It "works" but there is horrible distortion that sounds almost like crossover distortion when I engage the loop. Is this DC that I need to block with a cap? It looks like there is a .1uF 600V cap before the loop on the supposed Two-Rock "ruby" schematic I found online?

When looking at the ceriatone layout, I installed the loop between the .1uF cap and 1meg resistor that are connected with a jumper. (removed jumper and replaced with ZL Loop) This is located right in the center of the turret board for reference.

Could anyone shed some light on what I need to do here?

I am having trouble attaching the images here? The ceriatone layout can be found at:

http://www.ceriatone.com/tw-clone-expression/

The layout is under the downloads section

I have also posted pictures to the ZL Loop group on facebook if you would like to see the pictures that way.



Thank you in advance!