Why qml Audio does not use the default audio output? And how to force it to use the default output?

[Vladimir Sazonov]

I have two sound cards and Ubuntu 18.04. The audio output of one of them is selected as the default output in default.pa. My qml application has SoundEffect and Audio objects. SoundEffect outputs sound through the default output. But the Audio object outputs sound through the output of another card. Why? And how to force it to use the default output?

[mvuori]

(This doesn't sound like it has anything to do with mobile or embedded systems)