Make volume control logarithmic again

src/ui/MxcMediaProxy.cpp

@@ -43,7 +43,8 @@ MxcMediaProxy::MxcMediaProxy(QObject *parent)
               nhlog::ui()->debug("Set audio output");
               auto newOut = new QAudioOutput(this);
               newOut->setMuted(muted_);
-              newOut->setVolume(volume_);
+              newOut->setVolume(QAudio::convertVolume(
+                volume_, QAudio::LogarithmicVolumeScale, QAudio::LinearVolumeScale));
               setAudioOutput(newOut);
           }
       });

src/ui/MxcMediaProxy.h

@@ -59,7 +59,8 @@ public:
     {
         volume_ = val;
         if (auto output = audioOutput()) {
-            output->setVolume(val);
+            output->setVolume(QAudio::convertVolume(
+              val, QAudio::LogarithmicVolumeScale, QAudio::LinearVolumeScale));
         }
         emit volumeChanged();
     }