This only happens on multiplayer, not singleplayer, and only with the default HL2 weapons:
Notice how the gun spazzes the crap out when I shoot, and even holding it still it still twitches a bit. I’ve looked through my addons and have NO idea what is causing this. In fact, even my own srcds server has it! And yes I know I am playing a HL2RP gamemode but it also happens on my sandbox server. Help?