diff --git a/src/demoreader.h b/src/demoreader.h
--- a/src/demoreader.h
+++ b/src/demoreader.h
@@ -53,6 +53,10 @@ public slots:
     /// Sets the number of channels, this doesn't trigger a `numOfChannelsChanged` signal.
     void setNumOfChannels(unsigned value);
 
+signals:
+    // TODO: added for build only, remove later
+    void samplesPerSecondChanged(unsigned);
+
 private:
     bool paused;
     unsigned _numChannels;