diff --git a/src/audio_controller.h b/src/audio_controller.h
index 8cef88568..b7d560c39 100644
--- a/src/audio_controller.h
+++ b/src/audio_controller.h
@@ -115,6 +115,10 @@ class AudioController final : public wxEvtHandler {
 	/// @return The index of the first sample that is wholly inside the millisecond
 	int64_t SamplesFromMilliseconds(int64_t ms) const;
 
+	/// Get the duration of the currently open audio in milliseconds, or 0 if none
+	/// @return Duration in milliseconds
+	int GetDuration() const;
+
 public:
 	AudioController(agi::Context *context);
 	~AudioController();
@@ -161,10 +165,6 @@ public:
 	/// Returns 0 if playback is stopped. The return value is only approximate.
 	int GetPlaybackPosition();
 
-	/// Get the duration of the currently open audio in milliseconds, or 0 if none
-	/// @return Duration in milliseconds
-	int GetDuration() const;
-
 	/// @brief Get the primary playback range
 	/// @return An immutable TimeRange object
 	TimeRange GetPrimaryPlaybackRange() const;
diff --git a/src/audio_display.cpp b/src/audio_display.cpp
index ed664c0dc..8f086dc75 100644
--- a/src/audio_display.cpp
+++ b/src/audio_display.cpp
@@ -655,7 +655,7 @@ void AudioDisplay::SetZoomLevel(int new_zoom_level)
 	double cursor_time = (scroll_left + cursor_pos) * ms_per_pixel;
 
 	ms_per_pixel = new_ms_per_pixel;
-	pixel_audio_width = std::max(1, int(controller->GetDuration() / ms_per_pixel));
+	pixel_audio_width = std::max(1, int(GetDuration() / ms_per_pixel));
 
 	audio_renderer->SetMillisecondsPerPixel(ms_per_pixel);
 	scrollbar->ChangeLengths(pixel_audio_width, client_width);
@@ -1164,6 +1164,12 @@ void AudioDisplay::OnFocus(wxFocusEvent &)
 	RefreshRect(scrollbar->GetBounds(), false);
 }
 
+int AudioDisplay::GetDuration() const
+{
+	if (!provider) return 0;
+	return (provider->GetNumSamples() * 1000 + provider->GetSampleRate() - 1) / provider->GetSampleRate();
+}
+
 void AudioDisplay::OnAudioOpen(AudioProvider *provider)
 {
 	this->provider = provider;
@@ -1174,7 +1180,7 @@ void AudioDisplay::OnAudioOpen(AudioProvider *provider)
 	audio_renderer->SetAudioProvider(provider);
 	audio_renderer->SetCacheMaxSize(OPT_GET("Audio/Renderer/Spectrum/Memory Max")->GetInt() * 1024 * 1024);
 
-	timeline->ChangeAudio(controller->GetDuration());
+	timeline->ChangeAudio(GetDuration());
 
 	ms_per_pixel = 0;
 	SetZoomLevel(zoom_level);
diff --git a/src/audio_display.h b/src/audio_display.h
index e8c78e397..faaf403a9 100644
--- a/src/audio_display.h
+++ b/src/audio_display.h
@@ -228,7 +228,8 @@ class AudioDisplay: public wxWindow {
 	void OnMouseEnter(wxMouseEvent&);
 	void OnMouseLeave(wxMouseEvent&);
 
-	// AudioControllerAudioEventListener implementation
+	int GetDuration() const;
+
 	void OnAudioOpen(AudioProvider *provider);
 	void OnPlaybackPosition(int ms_position);
 	void OnSelectionChanged();