is this a bug ?

[gigi]

Hello guys,
I have a stereo bluetooth headphones with microphone and sometimes I use it for sunvox on the iPad.
But, today I discovered that if I put an input module in the song, in that moment the iPad swithes automaticaly the output to his speaker and the headphone are no more available for any app, while sunvox has an input module.
If I delete it, the iPad sometimes return to the headphone, but not always. And half of times I have to disconnect and reconnect the bluetooth headphones in order to make it available again.
Is this a bug ?
I want to use the headphone's microphone in sunvox. Is it possible ?
Thanks, Gigi.