iOS: Bluetooth headsets are not being detected as an input or output device in QtMultimedia

Both audioInput and audioOutput have dropdown boxes for selecting the
input and output which do not appear to function at all.

Test Procedure:

• Connect a Bluetooth headset to the iPad, Verify that you can switch
  outputs from the built-in music app. This is accomplished by using the
  "Control Center" which appears when you swipe up from the bottom of the
  screen. Notice also that a hardwired headset appears to automatically
  switch off the built-in speaker, and a choice for switching
  headphones/internal speaker does not generally appear in the Control
  Center in the case of hardwired outputs

• With the Bluetooth headset connected, start audioOutput sample.
  DropDown does not allow selection of outputs. Control Center does not
  allow selection of outputs.
• With the Bluetooth headset connected, start audioInput sample.
  Dropdown and Control Center do not allow selection of inputs.

I tested the behavior of some other audio apps on the iPad, and found
the following:

• Default Music App: Control Center can switch output.
• Garage Band: There is a menu setting in the app preferences that allow
  you to route the output to the Bluetooth headset. (no option in Control
  Center). When you do this, it tells you that recording is disabled on
  the Bluetooth input, presumably because performance is not good enough).
• Algoriddm DJAY (sample version) - Uses Control Center to select
  outputs.

What I think: Probably, audio should just respect the control center
selection, and selecting audio input/output from within the app is
superfluous in iOS
Also, It is clear that the application needs to do something to enable
selection of audio input/output in the control center.