Re-enable audio playback on reverse speed

Fixes #887

src/monitor/glwidget.cpp

@@ -1608,7 +1608,7 @@ void GLWidget::switchPlay(bool play, double speed)
         }
         double current_speed = m_producer->get_speed();
         m_producer->set_speed(speed);
-        if (speed <= 1. || speed > 6.) {
+        if (qFuzzyCompare(speed, 1.0) || speed < -6. || speed > 6.) {
             m_consumer->set("scrub_audio", 0);
         } else {
             m_consumer->set("scrub_audio", 1);