Hi Mark,
Don't feel guilty about anything--you provide so much assistance to so many of us, that's enough.  My reinstall didn't change anything, the animations are still intermittent.  The sound and muzzle flash of the M61 are synchronized sometimes, other times not and the muzzle flash stays on for a minute or so after the fire button is released.  On one occasion I had muzzle flash, recoil and smoke from the L60, most of the time sound and recoil only.  The M102 makes the sound and recoil everytime but never muzzle flashes or smokes.  I'll get into the config file and trace back to the effects and audio files for each animation and see if I can find the problem.