I am convinced it must have somthing to do with this new requirement in 4.4....
http://developer.android.com/about/vers ... d-4.4.html
Quote :
"
Important Behavior Changes
If you have previously published an app for Android, be aware that your app might be affected by changes in Android 4.4.
If your app reads from external storage...
Your app can not read shared files on the external storage when running on Android 4.4, unless your app has the READ_EXTERNAL_STORAGE permission. That is, files within the directory returned by getExternalStoragePublicDirectory() are no longer accessible without the permission. However, if you need to access only your app-specific directories, provided by getExternalFilesDir(), then you do not need the READ_EXTERNAL_STORAGE permission.
"