Prepare for segue with destination controller behaving differently on different IOS versions

Question

Hi I am developing one iPhone application. I am triggering segue and inside onprepare segue I am sending data to my next view controller.In storyboard my segue is pointing to navigation controller of my expected view controller and its back segue. So here is my issue :

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([[segue identifier] isEqualToString:@"mediaDetailSegue1"] || [[segue identifier]             isEqualToString:@"mediaDetailSegue2"])
{
    // this is working properly on below IOS 8 but not on IOS8
    MediaDetailViewController *mediaDetail = [segue destinationViewController];

    // this is working properly on IOS8 but not on below versions.
    MediaDetailViewController *mediaDetail = ([[segue destinationViewController]viewControllers][0]);
    mediaDetail.videoData = [_mediaContentArray objectAtIndex:selectedIndex];
    mediaDetail.isPlayVideo = isPlayVideo;
}
}

So as I mention in above code destination controller is not working properly for both versions.It is giving me following error:

for IOS8
 Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UINavigationController setVideoData:]: unrecognized selector sent to instance 0x176aa980'

for below IOS7
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[MediaDetailViewController viewControllers]: unrecognized selector sent to instance 0x14de8c00'

I can handle this situation according to versions but I want to know whether I am doing right or wrong.What is the proper way to handle this scenario? Need some help. Thank you.