the problem is uve got a build up of gunk on the inside of your coil packs. take them all out and either get a dremil drill and sand the inside of the coils lightly, or get some steel wool with some WD40 and clean the inside of them.
as electricity takes the quickest ("easiest") possible route to earth, because of the build-up inside the coil pack, the route to the spark plug is no longer the "easiest" route.. i used a dremil on mine and this is what they looked like after:
there was a big difference with before and after, now i get a damn good spark with no misfire.