diff --git a/sdrgui/gui/glspectrumview.cpp b/sdrgui/gui/glspectrumview.cpp
index c6cfb3e9e..04c2eafd2 100644
--- a/sdrgui/gui/glspectrumview.cpp
+++ b/sdrgui/gui/glspectrumview.cpp
@@ -975,7 +975,7 @@ void GLSpectrumView::paintGL()
     }
 
     QOpenGLFunctions *glFunctions = QOpenGLContext::currentContext()->functions();
-    glFunctions->glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+    glFunctions->glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
     glFunctions->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
     QMatrix4x4 spectrogramGridMatrix;