diff --git a/src/common/deps.rs b/src/common/deps.rs
index 8c89d84..f36920f 100644
--- a/src/common/deps.rs
+++ b/src/common/deps.rs
@@ -8,6 +8,7 @@ pub fn check_host_binaries(display: DisplayServer) -> Result<()> {
     if display == DisplayServer::Wayland {
         require("gst-launch-1.0")?;
         require("gst-inspect-1.0")?;
+        require("pactl")?;
         require_gst_element("pipewiresrc")?;
         require_gst_element("vah264enc")?;
         require_gst_element("h264parse")?;
@@ -61,6 +62,13 @@ fn install_hint_for_bin(bin: &str) -> String {
             Some("fedora" | "nobara") => "gstreamer1 gstreamer1-plugins-base-tools",
             _ => "gstreamer + tools",
         },
+        "pactl" => match distro.as_deref() {
+            Some("arch" | "cachyos" | "manjaro" | "endeavouros") => "libpulse",
+            Some("debian" | "ubuntu" | "pop" | "linuxmint") => "pulseaudio-utils",
+            Some("fedora" | "nobara") => "pulseaudio-utils",
+            Some("opensuse" | "opensuse-tumbleweed" | "opensuse-leap") => "pulseaudio-utils",
+            _ => "pulseaudio-utils (provides `pactl`)",
+        },
         _ => bin,
     };
     install_command(&distro, pkg)
diff --git a/src/host/wayland.rs b/src/host/wayland.rs
index 92a9986..bb30d0e 100644
--- a/src/host/wayland.rs
+++ b/src/host/wayland.rs
@@ -121,6 +121,8 @@ pub async fn start(opts: &HostOpts) -> Result<CaptureHandle> {
     //    no codec assumptions.
     let key_interval = (opts.framerate * 2).to_string();
     let bitrate = opts.bitrate.to_string();
+    let audio_monitor = default_audio_monitor().await?;
+    let audio_device = format!("device={audio_monitor}");
     let mut gst_cmd = Command::new("gst-launch-1.0");
     gst_cmd
         .args([
@@ -161,8 +163,10 @@ pub async fn start(opts: &HostOpts) -> Result<CaptureHandle> {
             "video/x-h264,stream-format=byte-stream,alignment=au",
             "!",
             "mux.",
-            // audio branch
+            // audio branch — capture the default sink's MONITOR (system audio
+            // out), not the default source (which is the mic).
             "pulsesrc",
+            &audio_device,
             "do-timestamp=true",
             "!",
             "queue",
@@ -274,3 +278,25 @@ pub async fn connect_to_capture(port: u16, max_wait: Duration) -> Result<TcpStre
         }
     }
 }
+
+async fn default_audio_monitor() -> Result<String> {
+    let output = Command::new("pactl")
+        .arg("get-default-sink")
+        .output()
+        .await
+        .context("failed to run `pactl get-default-sink` (install pulseaudio-utils or pipewire-pulse)")?;
+    if !output.status.success() {
+        bail!(
+            "pactl get-default-sink failed: {}",
+            String::from_utf8_lossy(&output.stderr).trim()
+        );
+    }
+    let sink = String::from_utf8(output.stdout)
+        .context("default sink name was not UTF-8")?
+        .trim()
+        .to_string();
+    if sink.is_empty() {
+        bail!("pactl get-default-sink returned no name (is a sound server running?)");
+    }
+    Ok(format!("{sink}.monitor"))
+}