AVPlayer Video SeekToTime

I'm using AVPlayer for play my video using slider and Some Buttons. Here is my methods for moving forward and backward using buttons.

-(IBAction)MoveForward
{
    //int value = timeSlider.value*36000 + 10;
    //CMTime newTime = CMTimeMakeWithSeconds(value, playspeed);
    //CMTime newTime = CMTimeMake(value,(playspeed*timeSlider.maximumValue));

    CMTime newTime = CMTimeMakeWithSeconds(timeSlider.value, playspeed);
    newTime.value += 60;
    [player seekToTime: newTime];
}

-(IBAction)MoveBackward
{
    CMTime newTime = CMTimeMakeWithSeconds(timeSlider.value-1, playspeed);
    [player seekToTime: newTime];
}

My Problem on this is the time to Seek is not working properly. That navigate to next frame based on seconds. I need to move next frame minutely. Help me...