diff --git a/aegisub/src/audio_box.cpp b/aegisub/src/audio_box.cpp
index 99057ef68dbbac39dd822fe35a5ef1d4483afd59..c711958af6d4f7ad66dd016db6360e27dd38bdc5 100644
--- a/aegisub/src/audio_box.cpp
+++ b/aegisub/src/audio_box.cpp
@@ -84,7 +84,7 @@ AudioBox::AudioBox(wxWindow *parent, agi::Context *context)
 , audio_open_connection(controller->AddAudioOpenListener(&AudioBox::OnAudioOpen, this))
 , panel(new wxPanel(this, -1, wxDefaultPosition, wxDefaultSize, wxTAB_TRAVERSAL | wxBORDER_RAISED))
 , audioDisplay(new AudioDisplay(panel, context->audioController, context))
-, HorizontalZoom(new wxSlider(panel, Audio_Horizontal_Zoom, OPT_GET("Audio/Zoom/Horizontal")->GetInt(), -50, 30, wxDefaultPosition, wxSize(-1, 20), wxSL_VERTICAL|wxSL_BOTH))
+, HorizontalZoom(new wxSlider(panel, Audio_Horizontal_Zoom, -OPT_GET("Audio/Zoom/Horizontal")->GetInt(), -50, 30, wxDefaultPosition, wxSize(-1, 20), wxSL_VERTICAL|wxSL_BOTH))
 , VerticalZoom(new wxSlider(panel, Audio_Vertical_Zoom, OPT_GET("Audio/Zoom/Vertical")->GetInt(), 0, 100, wxDefaultPosition, wxSize(-1, 20), wxSL_VERTICAL|wxSL_BOTH|wxSL_INVERSE))
 , VolumeBar(new wxSlider(panel, Audio_Volume, OPT_GET("Audio/Volume")->GetInt(), 0, 100, wxDefaultPosition, wxSize(-1, 20), wxSL_VERTICAL|wxSL_BOTH|wxSL_INVERSE))
 , mouse_zoom_accum(0)