Add an adjust-latency config option for PulseAudio

alsoftrc.sample

@@ -345,6 +345,14 @@ surround71 =
 #  PulseAudio server.
 #fix-rate = false
 
+## adjust-latency:
+#  Attempts to adjust the overall latency of device playback. Note that this
+#  may have adverse effects on the resulting internal buffer sizes and mixing
+#  updates, leading to performance problems and drop-outs. However, if the
+#  PulseAudio server is creating a lot of latency, enabling this may help make
+#  it more manageable.
+#adjust-latency = false
+
 ##
 ## ALSA backend stuff
 ##

utils/alsoft-config/mainwindow.cpp

@@ -387,6 +387,7 @@ MainWindow::MainWindow(QWidget *parent) :
     connect(ui->pulseAutospawnCheckBox, SIGNAL(stateChanged(int)), this, SLOT(enableApplyButton()));
     connect(ui->pulseAllowMovesCheckBox, SIGNAL(stateChanged(int)), this, SLOT(enableApplyButton()));
     connect(ui->pulseFixRateCheckBox, SIGNAL(stateChanged(int)), this, SLOT(enableApplyButton()));
+    connect(ui->pulseAdjLatencyCheckBox, SIGNAL(stateChanged(int)), this, SLOT(enableApplyButton()));
 
     connect(ui->jackAutospawnCheckBox, SIGNAL(stateChanged(int)), this, SLOT(enableApplyButton()));
     connect(ui->jackBufferSizeSlider, SIGNAL(valueChanged(int)), this, SLOT(updateJackBufferSizeEdit(int)));
@@ -855,6 +856,7 @@ void MainWindow::loadConfig(const QString &fname)
     ui->pulseAutospawnCheckBox->setChecked(settings.value("pulse/spawn-server", true).toBool());
     ui->pulseAllowMovesCheckBox->setChecked(settings.value("pulse/allow-moves", false).toBool());
     ui->pulseFixRateCheckBox->setChecked(settings.value("pulse/fix-rate", false).toBool());
+    ui->pulseAdjLatencyCheckBox->setChecked(settings.value("pulse/adjust-latency", false).toBool());
 
     ui->jackAutospawnCheckBox->setChecked(settings.value("jack/spawn-server", false).toBool());
     ui->jackBufferSizeLine->setText(settings.value("jack/buffer-size", QString()).toString());
@@ -1081,6 +1083,9 @@ void MainWindow::saveConfig(const QString &fname) const
     settings.setValue("pulse/fix-rate",
         ui->pulseFixRateCheckBox->isChecked() ? QString("true") : QString(/*"false"*/)
     );
+    settings.setValue("pulse/adjust-latency",
+        ui->pulseAdjLatencyCheckBox->isChecked() ? QString("true") : QString(/*"false"*/)
+    );
 
     settings.setValue("jack/spawn-server",
         ui->jackAutospawnCheckBox->isChecked() ? QString("true") : QString(/*"false"*/)

utils/alsoft-config/mainwindow.ui

@@ -53,7 +53,7 @@
      </rect>
     </property>
     <property name="currentIndex">
-     <number>5</number>
+     <number>0</number>
     </property>
     <widget class="QWidget" name="tab_3">
      <attribute name="title">
@@ -131,8 +131,8 @@ to stereo output.</string>
        <rect>
         <x>380</x>
         <y>20</y>
-        <width>80</width>
-        <height>20</height>
+        <width>93</width>
+        <height>29</height>
        </rect>
       </property>
       <property name="toolTip">
@@ -1185,6 +1185,9 @@ application or system to determine if it should be used.</string>
         <height>361</height>
        </rect>
       </property>
+      <property name="currentIndex">
+       <number>0</number>
+      </property>
       <widget class="QWidget" name="page">
        <widget class="QCheckBox" name="backendCheckBox">
         <property name="geometry">
@@ -1319,6 +1322,26 @@ rate to match the PulseAudio device.</string>
          <string>Fix Sample Rate</string>
         </property>
        </widget>
+       <widget class="QCheckBox" name="pulseAdjLatencyCheckBox">
+        <property name="geometry">
+         <rect>
+          <x>20</x>
+          <y>100</y>
+          <width>111</width>
+          <height>21</height>
+         </rect>
+        </property>
+        <property name="toolTip">
+         <string>Attempts to adjust the overall latency of device
+playback. Note that this may have adverse effects
+on the resulting internal buffer sizes and mixing
+updates, leading to performance problems and
+drop-outs.</string>
+        </property>
+        <property name="text">
+         <string>Adjust Latency</string>
+        </property>
+       </widget>
       </widget>
       <widget class="QWidget" name="page_7">
        <widget class="QCheckBox" name="jackAutospawnCheckBox">
@@ -2178,8 +2201,8 @@ added by the ALC_EXT_DEDICATED extension.</string>
        <rect>
         <x>160</x>
         <y>20</y>
-        <width>108</width>
-        <height>20</height>
+        <width>125</width>
+        <height>29</height>
        </rect>
       </property>
       <property name="sizeAdjustPolicy">
@@ -2348,7 +2371,7 @@ added by the ALC_EXT_DEDICATED extension.</string>
      <x>0</x>
      <y>0</y>
      <width>564</width>
-     <height>21</height>
+     <height>27</height>
     </rect>
    </property>
    <widget class="QMenu" name="menuFile">