trigger iOS7 mic prompt programatically in AIR3.8

Hi,

I'm trying a native extension to trigger the iOS7 mic prompt but it's not showing up as I expect.

This is what I call in my native extension

    if([[AVAudioSession sharedInstance] respondsToSelector:@selector(requestRecordPermission:)])
    {
         [[AVAudioSession sharedInstance] requestRecordPermission:^(BOOL granted){
           // blah
         }];
    }

Ideally I would like to be able to return whether it was granted or not. But when I tried it would always return FALSE

So then, I was just interested in triggering this popup first thing when my app starts and not handle whether the user granted access or not, but I am not seeing any popup where I call the native extension.

My app has not yet given access to the mic (I reset my device settings to ensure that and cannot see my app listed under Privacy->Microphone)

I'm using AIR3.8.

Anybody have any ideas?

Thanks!