[ErrorEvent type="error" bubbles=false cancelable=false eventPhase=2 text="Error #3004: Insufficient file space." errorID=3004]

This randomly happens on iOS 5 when I do addBitmapData to add photos to the Camera Roll. The device has got 4.6 gigabytes of free space. Sometimes it works fine, and sometimes it randomly fails and has this error.

This does not appear to be happening on my iPhone 5. As long as the photo access hasn't been disabled in privacy settings, the addBitmapData always seems to succeed.

Using AIR 3.5 beta, I think this was happening in 3.4 too though.

Why does it do this and how do I fix it?