After migration to Win 10 two weeks ago, I cannot see my audio device in "Speech Output Device" and all "Voices" fields are empty.
I have seen all of it shortly last weekend after I reinstalled ("repair") Cereproc, now I've lost them again.

I checked sapi.cpl, TTS, Speech-to-text, Windows Default Device and Default Communication Device, they all seem ok to me.

Interestingly, I see my sound device in the AppConfig.xml
  <AppSetting>
    <Name>SpeechOutputDeviceName</Name>
    <Value>Kopfhörer (Sennheiser PC 8.2 USB)</Value>
    <LastChanged>2022-04-03T22:00:25.722796+02:00</LastChanged>
  </AppSetting>
  <AppSetting>
    <Name>SpeechOutputDeviceIndex</Name>
    <Value>1</Value>
    <LastChanged>2022-04-03T22:00:25.722796+02:00</LastChanged>
  </AppSetting>
and also the selected voices.

The last entries in the Trace_File.log is
FPL Control Loaded
Value cannot be null.
Parameter name: item
   at System.Windows.Forms.ComboBox.ObjectCollection.AddInternal(Object item)
   at System.Windows.Forms.ComboBox.ObjectCollection.AddRangeInternal(IList items)
   at System.Windows.Forms.ComboBox.ObjectCollection.AddRange(Object[] items)
   at P2A2021.frmConfig.LoadVoiceSettings()
   at P2A2021.frmConfig.c80274a89e27740d41ca5ea0a996692a1(Object cb25b07786a6e786dea76cf87175f59f0, EventArgs cb4d4bf05d278f00a41fc902f6c5d26a2)
   at System.Windows.Forms.Form.OnLoad(EventArgs e)
   at System.Windows.Forms.Form.OnCreateControl()
   at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
   at System.Windows.Forms.Control.CreateControl()
   at System.Windows.Forms.Control.WmShowWindow(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.Form.WmShowWindow(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
Simulator Disconnected. 04/03/2022 21:55:01
Application frmP2AMain ended normally 04/03/2022 21:55:02
Object of type SlimDX.DirectInput.Joystick was not disposed. Stack trace of object creation:
Total of 1 objects still alive.

I did a fallback overwrite installation from beta2n to beta2m, nothing changed.

Before I remove and reinstall P2A, maybe a hint what's going on wrong in my box ?
And just some questions:

Does P2A need Prepar3d running to test the voices in the config menu ?
(As I remember, the voice testing worked stand-alone ?!?)

Does P2D select the audio device from P3D ?
P3D sees the audio devices correctly: default device is Realtek stereo (Speaker pair), default comm devices is my Sennheiser USB headphone.

I'm clueless...

 

Sorry for the post...as the whole sunday now passed, I found the reason:

Migration of Win 7 to 10 took over my voice entries from additional voice packs, but not the voice packs that belong to this voices.
So the Win 10 registry contained some voice entries without their voice packs.
The dialog Settings - Time&Language - "Speech" showed such voices but simply didn't play them.
P2A's reaction was to refuse showing any "Voice" neither the audio device in its menus.

After I downloaded the voice packs of these "inaudible" voices, Windows Speech played them
and P2A showed the correct config entries in "Voices" and "Speech Output Device".