diff --git a/cosmic-applet-audio/src/lib.rs b/cosmic-applet-audio/src/lib.rs
index bd62dfbd..7647100d 100644
--- a/cosmic-applet-audio/src/lib.rs
+++ b/cosmic-applet-audio/src/lib.rs
@@ -111,6 +111,21 @@ impl Audio {
             "microphone-sensitivity-high-symbolic"
         }
     }
+
+    /// Refresh the volume ceilings and slider breakpoints from the
+    /// amplification config.
+    ///
+    /// Must run at startup, not only when the popup opens: the
+    /// scroll-to-adjust handler clamps against `max_sink_volume`, which
+    /// `Default` leaves at 0. Until the popup had been opened once, every
+    /// wheel event therefore resolved to `SetSinkVolume(0)`.
+    fn refresh_volume_limits(&mut self) {
+        (self.max_sink_volume, self.sink_breakpoints) =
+            if amplification_sink() { (150, &[100][..]) } else { (100, &[][..]) };
+
+        (self.max_source_volume, self.source_breakpoints) =
+            if amplification_source() { (150, &[100][..]) } else { (100, &[][..]) };
+    }
 }
 
 #[derive(Debug, PartialEq, Eq, Default)]
@@ -256,13 +271,13 @@ impl cosmic::Application for Audio {
     const APP_ID: &'static str = "com.system76.CosmicAppletAudio";
 
     fn init(core: cosmic::app::Core, _flags: ()) -> (Self, app::Task<Message>) {
-        (
-            Self {
-                core,
-                ..Default::default()
-            },
-            Task::none(),
-        )
+        let mut app = Self {
+            core,
+            ..Default::default()
+        };
+        app.refresh_volume_limits();
+
+        (app, Task::none())
     }
 
     fn core(&self) -> &cosmic::app::Core {
@@ -295,17 +310,7 @@ impl cosmic::Application for Audio {
                     let new_id = window::Id::unique();
                     self.popup.replace(new_id);
 
-                    (self.max_sink_volume, self.sink_breakpoints) = if amplification_sink() {
-                        (150, &[100][..])
-                    } else {
-                        (100, &[][..])
-                    };
-
-                    (self.max_source_volume, self.source_breakpoints) = if amplification_source() {
-                        (150, &[100][..])
-                    } else {
-                        (100, &[][..])
-                    };
+                    self.refresh_volume_limits();
 
                     let mut popup_settings = self.core.applet.get_popup_settings(
                         self.core.main_window_id().unwrap(),