Interaction between volume pot and passive tone stack

[David]

I did several searches regarding passive tone stacks and couldn't get a concrete answer, so I'm going to frame the question to get the information the way I need it.

Several months ago, I found myself having to use a "scooped mids" type of distortion.  I was able to do this by doing the scooping on a graphic equalizer.  The downside was having to kick in and kick out two pedals when it came time for distortion.  This is a bit much.  I thought it would be convenient to have distortion with a tone stack so I only needed to kick in one pedal.

I decided to do this by building a Smash Drive with the passive tone stack.  I had successfully breadboarded this unit, but hadn't been able to build one because of early problems I had with packaging.  I still dislike construction without PCBs and I still hate packaging -- but they're becoming a little more manageable.  Anyway, I got the board built, and decided to do the tone stack and volume control wired point to point.

It's all wired up and boxed.  Everything SEEMS to work.  There's something (maybe two somethings) going on, though.  I've noticed that I don't get anything approaching full output unless I have the BASS control fully CCW.  Well, dang!  This kind of defeats the purpose of a tone stack.  Also, I have a 500K pot hanging off the tone stack for an output volume control.  This thing seems to have a dead spot in the middle.  It's moderately loud CCW and fairly loud CW.  All right.  As R.G. would say, Ma Nature is trying to tell me something.  I'm listening, but I don't think she's speaking in English.  Now, one telling point here is that I initially put it together without the status indicator LED.  Tests with that configuration had utterly OUTRAGEOUS output.  I noticed the volume dropped off significantly after installing the LED indicator.  I have not looked, but it is possible that something in my point-to-point, hardwired tone stack (and yes, I stupidly used solid wire on the tone stack) is shorting to the box.  Would this account for the interactivity between the tone stack and volume control?  My guess is that it would account for some of the volume drop because signal is being shorted to ground.  Is that true?