Just picked up this little Fuzz Face and loving it so far. Only thing is I have to dime the volume to reach unity, which gives me no headroom if I want to boost my signal. I read these have an internal trim control that I can adjust bias for more gain and/or headroom, but I can't seem to find it. Maybe the silicone version doesn't have this? If not, is there an easy mod to add more volume to this pedal?