objective c - Load images to cache- make the iPad crash -

i loading many images cache, worked great in simulation till now, have tried on device - ipad2 , , crash, if after default screen loading sprites cache . app crash before starts .

so , have tried load on background , , happen that, not crash now, some-how see black rects instead of images have loaded cache , means maybe havnt loaded anyway .

this in init method of first class :

[self performselectorinbackground:@selector(loadspriteframes) withobject:nil]; 

//than

-(void)loadspriteframes {      //pre load effects       [[simpleaudioengine sharedengine] preloadeffect:@"badeffect.mp3"];       [[simpleaudioengine sharedengine] preloadeffect:@"hearteffect.mp3"];       [[simpleaudioengine sharedengine] preloadeffect:@"rewardbig.mp3"];        [[simpleaudioengine sharedengine] preloadbackgroundmusic:@"backgroundtraffic.mp3"];       //preload images needed animations        [[cctexturecache sharedtexturecache] addimage:@"stopanim.png"];       [[cctexturecache sharedtexturecache] addimage:@"shanim.png"];       [[cctexturecache sharedtexturecache] addimage:@"happyanim.png"];       [[cctexturecache sharedtexturecache] addimage:@"grumpyanim.png"];     nslog(@"*****2"); //do log  }