To debug effectively:

[petemoore]

  I suggest...Filling in all the * lines.
  I've put this in 'testing', anytime someone would like to use it as a template..ie get rid of all the *'s as you fill in the information.
Name and show link to circuit schematic.
  *Garfunkels accoustic pre-amp
  If you're using a layout or PCB post a link to that too.
  *GAPP layout
   Is there a connection between circuit power supply V+ and Gnd. under any of all power supply 'conditions' ie...is there shorting under and 'normal' switching conditions of input jack or DC jack or any other time?
  *YES   /    NO  [enter comments
  Measure battery voltage.
  *X.X2VDC
  Measure battery voltage with circuit loading
  *X.21VDC
If using a power supply, what does it say on it about voltage rating?
  *Xvolt
  Also name power supply type
  *AC  or DC output
  test the voltage of the power supply.
  *9.2VDC
  Test votlage of power supply with circuit connected
  * .22vdc
  Is the circuit npn-negative ground?
  *Transistor type [npn/pnp...jfet, mosfet, Ge, etc.
  *Circuit polarity [neg gnd. or pos. ground?
  *Opamp type [Dual, single, OTA, CMOS...other
  connect DMM to ground, and test for continuity at every point in the schematic with a ground symbol, from the most 'distant' [test points should be beyond all connections and solder joints].
  Test the cables that are plugged if they can be plugged in, at the plug sleeves which connect to guitar and amp
  Is there continuity at all 'distant circuit ground points
  Stage 2
  Connect power supply, if there is a large current draw [ie voltage drops by 10% or more, disconnect power and post that result].
  Is there a >10% voltage drop in battery when circuit is connected?
  *Yes  /  No
  What voltages are measured [using ground as reference voltage =O.0V], using DMM at all active component pins?
  *Dual opamp
*1  4.5v
*2  4.5v
*3  4,5v
*4  0.0v
*5  4.5v
*6  4.5v
*7  4.5v
*8  9v
-----
  *Single opamp
*1  NC
*2  4.5v
*3  4.5v
*4  0.0v
*5  NC
*6  4.5v
*7  9v
*8  NC
-----
*Transistor type
  *NPN
  *PNP
  *Jfet/mosfet/BJT/Ge?
  *Transistor part #
  *Data sheet pinout information
  Pin Voltage
  *D 9v         
  *G 2.2V
  *S  .21V
  Or substitue 'E/B/C if using bipolar transitor
  List any pertinent comments and questions.
  Stage 3
Audio probe, and list results and comments.
  Test that all stages are 'separated' by DC blocking capacitors,
  Can you physically see that a capacitor is properly wired to the input and output of each active component stage? ie signal path must go through the cap to enter or exit the active stage.
  The circuit debugging may have limited results if the answers with * are not known or posted.
  BTW the opamp pins for most distorters [gain stages] are more than optimal, bias is 'centered' at 1/2 the power supply, except for the power supply pins [the 9v and 0.0v ones.
  Please feel free to add, correct or comment !