For me, the Screen just flickers when I'm ingame and I get a huge headache :( It does pick up on the smartphone movement on the minimap, but the ball wont move

For me, the Screen just flickers when I'm ingame and I get a huge headache :( It does pick up on the smartphone movement on the minimap, but the ball wont move… I can jump tho. Any ideas? (OSX 10.6.8, Chrome Version 25.0.1364.172 // iPhone 4 10.6.2, Chrome Version 25.0.1364.124)