distributor problem

I have a problem with my distributor. The symptoms are truck runs great until it warms up. Then it seems there are shocking noises with in the distributor cap. Like the cap is being electrically charged. This happens only if I rev the truck above the 3000 rpm. My tach starts to get all wacked out, lose of power, and after it goes down to idle noise goes away and runs fine. Any ideas? I have MSD 6A, 8910EIS, and new distributer, cab, rotor, wire, plugs. I have checked all the wiring, msd, tech adapter. Help! Thanxs

post deleted

Yes, the distributor is a stock replacement. Mine burnt up when my choke got stuck and ran lean causing my truck to over heat. The coil is a blaster 2 coil and I have never had a problem until I replaced the distributor. When I drilled a holed in the cap I can see that there more spark then normal. It seems to only happen when I have a load on the truck or above 300 rpm's. I'm so stuck!