diff --git a/site/docs/install/t480.md b/site/docs/install/t480.md
index 44f3297..17b090e 100644
--- a/site/docs/install/t480.md
+++ b/site/docs/install/t480.md
@@ -493,6 +493,9 @@ you've inserted manually.
 If it says "Unplugged", try it anyway. The HDA Verb may be incorrect. This
 will be investigated and a hotfix patch made to the Libreboot 20241206 images.
 
+You must also be used *pulseaudio*, not *pipewire*, because even manual
+switching doesn't work in pipewire. **It only works in pulseaudio.**
+
 ### How to use HDMI audio
 
 You can get audio from Displayport/HDMI, but you must select it manually.