Tweaks for Lower Noise in YJM-308?

[zombiwoof]

Just wondering if anyone has found any component subs to lower the noise in the YJM-308 pedal.  It already has a low-noise op-amp in it (rc4558), but would replacing any of the caps or resistors help to reduce the hiss in this thing, without losing the basic flavor?  I really like the sound of it, but would like to quiet it down a bit.

Thanks,
Al