From 0de812b7b52df114c66fafd5e919962044550490 Mon Sep 17 00:00:00 2001
From: amer cerkic <amer@highfidelity.io>
Date: Tue, 26 Nov 2019 11:41:41 -0800
Subject: [PATCH] waiting on local injector prep

---
 libraries/audio-client/src/AudioClient.cpp | 7 ++++++-
 libraries/audio-client/src/AudioClient.h   | 4 +++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/libraries/audio-client/src/AudioClient.cpp b/libraries/audio-client/src/AudioClient.cpp
index 5502986cff..4080019822 100644
--- a/libraries/audio-client/src/AudioClient.cpp
+++ b/libraries/audio-client/src/AudioClient.cpp
@@ -2064,6 +2064,11 @@ bool AudioClient::switchOutputToAudioDevice(const HifiAudioDeviceInfo outputDevi
     Lock localAudioLock(_localAudioMutex);
     _localSamplesAvailable.exchange(0, std::memory_order_release);
 
+    //wait on local injectors prep to finish running
+    if (_localPrepInjectorFuture.isStarted() || _localPrepInjectorFuture.isRunning()) {
+        _localPrepInjectorFuture.waitForFinished();
+    }
+
     // cleanup any previously initialized device
     if (_audioOutput) {
         _audioOutputIODevice.close();
@@ -2344,7 +2349,7 @@ qint64 AudioClient::AudioOutputIODevice::readData(char * data, qint64 maxSize) {
     }
 
     // prepare injectors for the next callback
-    QtConcurrent::run(QThreadPool::globalInstance(), [this] {
+    _audio->_localPrepInjectorFuture = QtConcurrent::run(QThreadPool::globalInstance(), [this] {
         _audio->prepareLocalAudioInjectors();
     });
 
diff --git a/libraries/audio-client/src/AudioClient.h b/libraries/audio-client/src/AudioClient.h
index e31b4789ce..09abb2c356 100644
--- a/libraries/audio-client/src/AudioClient.h
+++ b/libraries/audio-client/src/AudioClient.h
@@ -18,6 +18,7 @@
 #include <mutex>
 #include <queue>
 
+#include <QFuture>
 #include <QtCore/QtGlobal>
 #include <QtCore/QByteArray>
 #include <QtCore/QElapsedTimer>
@@ -506,7 +507,8 @@ private:
 #endif
 
     AudioSolo _solo;
-
+    
+    QFuture<void> _localPrepInjectorFuture;
     QReadWriteLock _hmdNameLock;
     Mutex _checkDevicesMutex;
     QTimer* _checkDevicesTimer { nullptr };