Tone Bender MK1.5 problem

[mgmg]

Hi, i have a Tone Bender MK1.5 with 2 OC75 transistor and i have some question about it.

Q1 C 0.33v
Q2 C 5.86v

When i play a chord or a single note ( example E string ) and let the sound playing, the tone bender has a discrete or quite long sustain but the sound tends to oscillate. The tone bender has no background noises or something else and sounds amazing, but with the attack pot at 90%-100% i have this thing. Is it ok? Maybe the transistors are note biased correctly?
Thank you so much.

[Electric Warrior]

I'd expect Q2C to be a bit higher with Q1C sitting at 0.33V, but I doubt that's what causes the oscillation. How gainy are your transistors? Some OC75s can be quite hot. Your wiring or layout are also likely culprits.

[mgmg]

New bias voltages q1c 0.31v q2c 7.56v, it sounds amazing but i also have the problem with some notes.
Transistor hfe are 61 q1 with 0.04 leak and 89 for q2 with 0.03 leak.
Wiring is ok and there are not bad connection. Layout is Classic pnp tone bender mk1.5, i also made 4 pedals with that schematics and never had this problem

[Electric Warrior]

The voltages look just like expected now. Hfes are totally reasonable. Maybe it's a wiring issue?