So I have been tackling this problem over the past week. My problem was even though I would get 60+ fps in game my OBS was only pushing 20fps to my stream. I had tried everything underneath the sun to try and fix it; re-seat my LGHD, rollback the version of OBS I had, tried different games, reset all my scenes, messed w/ all my stream settings etc etc. Nothing was fixing the problem, then I noticed I had Aero disabled on startup check. Back of my mind I thought it couldn't POSSIBLY be that..... well it was. The immediate next test I tried I had a nice smooth 60fps stream again, sometimes it's the littlest thing that can cause such a huge problem. If you have an Avermedia Live Gamer HD just make sure you have Aero ENABLED when streaming and you wont have this problem!