Qt-C++ based library on Android using JNI , missing initialization of Qt libs?

[dualfaces]

Hi all,

i have written a c++ library containing Qt based classes. They handle sound input and output using QAudioInput and QAudioOutput. To use it in an Android application I use a c method interface which is called by JNI functions.
Calling the functions of the c interface work fine, i can see debug output in Logcat. But when the library tries to instantiate a QAudioInput or QAudioOutput it says that there are no available output devices.
On a Windows PC using a java application all is good, hence i expect that there is some "magic" initialization code in the QtActivity.java class which i don't use.

Are there functions that can just be called in order to set up the environment such that Qt classes work?

Thank you!

Regards,
Andreas