Qt intermittently will hang trying to lock mutex when Image is loaded from URL

Intermittently Qt will hang for several seconds while trying to destroy a screen while images are loading.

mainTrace.txt is the stack trace of the main thread while the application is non-responsive threadTrace.txt is the stack trace of the other thread we believe is accessing the QML Engine mutex.

If NetworkAccessManager is created and added to engine before loading the QML then the issue does not manifest.

It's hard to reproduce, desktop PC with SuSE 11 is needed. Qt was installed using the 32-bit installer provided by Digia. Using the example code that was provided the issue occurs less frequently than with our full application, but I can still usually get it to occur at least once every dozen or so attempts.

Following bugs can be related to this:
https://bugreports.qt-project.org/browse/QTBUG-39288
https://bugreports.qt-project.org/browse/QTBUG-39024
https://bugreports.qt-project.org/browse/QTBUG-27809