i use the .032" 60/40 rosin core solder from radio shack.
so far i've replaced the input jacks and bridge pups in both
my RGs, made various instrument/multi conductor cables
with it and added a highly-liquid msa-r midi relay to my
i'm not ultra savvy with electronics, more like a jerk-off
who likes to tinker with gear. but, i'd venture that the buzz
your experiencing is linked to some other culprit. perhaps
a bad solder joint???
i am certain though, that cleanly terminated joints are important.