I found out "Silent switch" status of Device using "AudioSessionGetProperty" before [iOS5] released.
CFStringRef route;
UInt32 propertySize = sizeof(CFStringRef);
AudioSessionInitialize(NULL, NULL, NULL, NULL);
AudioSessionGetProperty(kAudioSessionProperty_AudioRoute, &propertySize, &route);
if(CFStringGetLength(route) == 0) {
// Silent Mode
}
Now, I'd like to know how to get "silent switch" status in "iOS5"