Android AudioIODevice::open() returns no error but the callback is never called if device is busy

I am trying to open device for input (partual code):

mLastError = (mDevice->open(Channels, BigInteger(), mStreamFormat.SamplingFrequency,

The device mDevice is properly created and initialized before.

Everything works fine except when the device is already open by another application. In this case open() returns empty string indicating no error, but no data is ever recieved and the callback is never called.

Is it a juce bug or how should I know that the certain device is busy and cannot be open?

Android 4.4 & Juce 3.0.8