diff --git a/src/spek-spectrogram.cc b/src/spek-spectrogram.cc
index 970f462..98e4cbc 100644
--- a/src/spek-spectrogram.cc
+++ b/src/spek-spectrogram.cc
@@ -25,6 +25,7 @@
 #include "spek-spectrogram.hh"
 
 BEGIN_EVENT_TABLE(SpekSpectrogram, wxPanel)
+    EVT_IDLE(SpekSpectrogram::on_idle)
     EVT_PAINT(SpekSpectrogram::on_paint)
     EVT_SIZE(SpekSpectrogram::on_size)
 END_EVENT_TABLE()
@@ -73,6 +74,11 @@ void SpekSpectrogram::save(const wxString& path)
 {
 }
 
+void SpekSpectrogram::on_idle(wxIdleEvent& evt)
+{
+    Update();
+}
+
 void SpekSpectrogram::on_paint(wxPaintEvent& evt)
 {
     wxAutoBufferedPaintDC dc(this);
@@ -176,6 +182,7 @@ void SpekSpectrogram::pipeline_cb(int sample, float *values, void *cb_data)
     }
 
     s->Refresh(); // TODO: refresh only one pixel column
+    wxWakeUpIdle();
 }
 
 
diff --git a/src/spek-spectrogram.hh b/src/spek-spectrogram.hh
index 2a9b52a..9158db3 100644
--- a/src/spek-spectrogram.hh
+++ b/src/spek-spectrogram.hh
@@ -31,6 +31,7 @@ public:
     void save(const wxString& path);
 
 private:
+    void on_idle(wxIdleEvent& evt);
     void on_paint(wxPaintEvent& evt);
     void on_size(wxSizeEvent& evt);
     void render(wxDC& dc);