diff --git a/web/index.html b/web/index.html
index bf1935c..384cc59 100644
--- a/web/index.html
+++ b/web/index.html
@@ -30,9 +30,9 @@ <h1>OpenStudio</h1>
 
     <!-- Controls section -->
     <section id="controls">
-      <button id="start-session">Start Session</button>
+      <button id="start-session">Start Broadcast</button>
       <button id="toggle-mute" disabled>Mute</button>
-      <button id="end-session" disabled>End Session</button>
+      <button id="end-session" disabled>End Broadcast</button>
     </section>
 
     <!-- Recording Controls -->
diff --git a/web/js/main.js b/web/js/main.js
index c117569..7d994b4 100644
--- a/web/js/main.js
+++ b/web/js/main.js
@@ -78,6 +78,12 @@ class OpenStudioApp {
     // Check for room ID in URL hash
     this.checkUrlHash();
 
+    // Update CTA if joining an existing room
+    if (this.roomIdFromUrl) {
+      this.startSessionButton.textContent = 'Join Broadcast';
+      this.endSessionButton.textContent = 'Leave Broadcast';
+    }
+
     // Auto-connect to signaling server
     this.initializeApp();
 
@@ -821,6 +827,8 @@ class OpenStudioApp {
     this.recordingTracksDiv.style.display = 'none';
     this.lastRecordings = null;
     window.location.hash = '';
+    this.startSessionButton.textContent = 'Start Broadcast';
+    this.endSessionButton.textContent = 'End Broadcast';
 
     // Reconnect to signaling
     this.signaling.connect();