vsync slowing some games down

[drhycodan]

There are probably more, but a good example of this is metal gear twin snakes. In the tanker level, with vsync on, the game runs smooth and then slows down to a crawl to a few seconds and then goes back to full speed again. The weird thing is, the emulator still thinks the game is running full speed during that vsync "lagging" and so the music stays normal. With vynsc off, the game runs smooth without any slowdowns but at the cost of screen tearing.