Fuzz Face fuzz pot problem?

[Filip_Mikuz]

hi!

ive built a fuzzface and it works except for when i turn the fuzz nob to about 90%. When the fuzz switches to radio oscillation at one particular point the fuzz loses most of its fuzz and volume, but then when i turn it foward again, it comes back. And when i turn it to 100% the sound starts to wobble in fuzz and volume. what could it be?
could it be that the pot has a problem or are there greater powers at play here?
the fuzz face is bc108 with adjustable bias(4.5v) and it runs on a PS.

I thank you in advance for help.

[Elijah-Baley]

Start to to measure the fuzz pot with the multimeter and see if it works well. If you can replace it. What is its value?
Check well the values and the orientations of all components.

[Filip_Mikuz]

oriantation is ok. i checked the resistance it went from  1.20-0.16 and then it jumped to 0.22 and then to zero.

[Elijah-Baley]

Maybe there's a mistake somewhere.
Are you using a board? PCB, stripboard or something else?
You should to test the circuit on a breadboard.

[Ground Control]

Try installing a small cap (27pF) from Base to Collector of Q2 (Fuzz stage).

This reduces the gain for high frequencies and is supposed to help reduce oscillations at high gain settings.