Fix playlist clips have no audio regression.

Fixes #816

src/lib/audio/audioStreamInfo.cpp

@@ -16,7 +16,7 @@ the Free Software Foundation, either version 3 of the License, or
 #include <QString>
 #include <cstdlib>
 
-AudioStreamInfo::AudioStreamInfo(const std::shared_ptr<Mlt::Producer> &producer, int audioStreamIndex)
+AudioStreamInfo::AudioStreamInfo(const std::shared_ptr<Mlt::Producer> &producer, int audioStreamIndex, bool playlist)
     : m_audioStreamIndex(audioStreamIndex)
     , m_ffmpegAudioIndex(0)
     , m_samplingRate(48000)
@@ -25,6 +25,10 @@ AudioStreamInfo::AudioStreamInfo(const std::shared_ptr<Mlt::Producer> &producer,
 {
     // Fetch audio streams
     int streams = producer->get_int("meta.media.nb_streams");
+    if (playlist) {
+        // Playlist clips do not provide stream info
+        m_audioStreams.insert(0, i18n("Audio"));
+    }
     int streamIndex = 1;
     for (int ix = 0; ix < streams; ix++) {
         char property[200];

src/lib/audio/audioStreamInfo.h

@@ -23,7 +23,7 @@ class AudioStreamInfo
 {
 public:
     // TODO make that access a shared ptr instead of raw
-    AudioStreamInfo(const std::shared_ptr<Mlt::Producer> &producer, int audioStreamIndex);
+    AudioStreamInfo(const std::shared_ptr<Mlt::Producer> &producer, int audioStreamIndex, bool playlist = false);
     ~AudioStreamInfo();
 
     int samplingRate() const;

src/mltcontroller/clipcontroller.cpp

@@ -262,7 +262,7 @@ void ClipController::getInfoForProducer()
         m_clipType = ClipType::Unknown;
     }
     if (audioIndex > -1 || m_clipType == ClipType::Playlist) {
-        m_audioInfo = std::make_unique<AudioStreamInfo>(m_masterProducer, audioIndex);
+        m_audioInfo = std::make_unique<AudioStreamInfo>(m_masterProducer, audioIndex, true);
         // Load stream effects
         for (int stream : m_audioInfo->streams().keys()) {
             QString streamEffect = m_properties->get(QString("kdenlive:stream:%1").arg(stream).toUtf8().constData());