[experimental, audio] try to avoid taskbar MIC flickering

* sometimes the MIC icon in the windows task bar is flickering (on/off)
* this workaround tries to avoid this

src/blacksound/audioutilities.cpp

@@ -8,10 +8,13 @@
 
 #include "audioutilities.h"
 #include "blackmisc/audio/audiodeviceinfolist.h"
+#include "blackconfig/buildconfig.h"
+
 #include <QStringBuilder>
 #include <QAudioInput>
 #include <QAudioOutput>
 
+using namespace BlackConfig;
 using namespace BlackMisc::Audio;
 
 namespace BlackSound
@@ -245,4 +248,10 @@ namespace BlackSound
         return static_cast<qreal>(normalize0to100(in));
     }
 
+    void occupyAudioInputDevice()
+    {
+        if (!CBuildConfig::isRunningOnWindows10()) { return; }
+        static const QAudioInput input(QAudioDeviceInfo::defaultInputDevice());
+    }
+
 } // ns

src/blacksound/audioutilities.h

@@ -41,6 +41,8 @@ namespace BlackSound
     BLACKSOUND_EXPORT qreal  normalize0to100qr(double in);
     //! @}
 
+    //! Open a input device
+    BLACKSOUND_EXPORT void occupyAudioInputDevice();
 } // ns
 
 #endif // guard

src/swiftguistandard/swiftguistdinit.cpp

@@ -30,6 +30,7 @@
 #include "blackcore/webdataservices.h"
 #include "blackcore/context/contextnetwork.h"
 #include "blackcore/context/contextsimulator.h"
+#include "blacksound/audioutilities.h"
 #include "blackmisc/network/networkutils.h"
 #include "blackmisc/loghandler.h"
 #include "blackmisc/logmessage.h"
@@ -72,9 +73,11 @@ void SwiftGuiStd::init()
     m_mwaStatusBar = &m_statusBar;
     m_mwaOverlayFrame = ui->fr_CentralFrameInside;
     m_mwaLogComponent = ui->comp_MainInfoArea->getLogComponent();
-
     sGui->initMainApplicationWidget(this);
 
+    // experimental: avoid mic flickering
+    if (CBuildConfig::isLocalDeveloperDebugBuild()) { BlackSound::occupyAudioInputDevice(); }
+
     // log messages
     m_logSubscriber.changeSubscription(CLogPattern().withSeverityAtOrAbove(CStatusMessage::SeverityInfo));