Popping sound in a fuzz face build

[Electric Eel]

Hello

I'v been trying to put together a fuzz face with silicon transistors, but i'm having some trouble with it.

The bypass works fine, but when i 'engage' the fuzz-effect i experience 2 problems:
- there is no fuzz, its just a clean sound with lots of buzzing/noise (probably from a grounding issue?)
- there is a popping sound (it goes 'pop' every second or so)

I've allready done some testing with the DMM and i found that the popping comes from the voltage constantly switching between 2 values at various points in the circuit. My (basic) knowledge of electronics leads me to believe that this is probably caused by one of the capacitors constantly charging/discharging?

Some voltages:

V at negative side of C1: constantly hops from 4.7V to 5.1V
V at positive side of C1: always at 0.55V

Q1
C = 0.7V - 1.3V
B = 0.55V
E = 0V

Q2
C= 0.65V - 3.11V
B= 0.66V - 1.3V
E= 0.4V - 0.6V

Ofcourse, the main question is: how can i solve this problem?

Link to the schematic/breadboard layout: http://www.smallbearelec.com/HowTos/BreadboardSiFF/BreadboardSiFF.htm

[guitarify]

Well, I'm kind of a noob myself, but I recently built that same board with no problems. Is this still on the breadboard or have you gone to the next tutorial and soldered it all together? Did you swap out the cap to make sure it wasn't bad? If soldered, check the joints and make sure you don't have too much solder on something that is shorting the connection.
Try an audio probe to see if the signal is getting past that first cap.
Did you go all the way through the article and make the suggested changes? Your collector voltages are way too low  so you need to adjust the bias. Though maybe the low voltage is being caused by whatever is making the voltage fluctuate on C1?

[G]

V at negative side of C1: constantly hops from 4.7V to 5.1V

You may have got the ground and signal wires the wrong way round; this could lead to the input capacitor charging and discharging.

[Electric Eel]

V at negative side of C1: constantly hops from 4.7V to 5.1V

You may have got the ground and signal wires the wrong way round; this could lead to the input capacitor charging and discharging.

Yup, that was the problem. Thanks for the help guys!