iPhone OS4 alarm clock

I have read many posts and still i cannot achieve the desired functionality while my application is suspended in the background.

My reference point is this radio alarm application.

The things i cannot do using local notifications (which are successfully implemented开发者_开发百科 in the radio clock above) are:

1. play alarm sound in the background while phone is muted
2. change phone volume.
3. play mp3 songs.

Also i noticed that they are able to play sounds longer than 30 seconds and even radio as alarm sounds which probably means that local notifications are not being used (audio-wise)

any insight would be appriciated...

---

The reason that this Radio App succeeds in playing a long audio file , is that it actually plays a background silent loop audio while waiting for the alarm .

IMO that's the reason people complain it drains the battery.