diff --git a/ElementX/Sources/Services/ElementCall/ElementCallService.swift b/ElementX/Sources/Services/ElementCall/ElementCallService.swift
index 980e9b5f3..9555d62e8 100644
--- a/ElementX/Sources/Services/ElementCall/ElementCallService.swift
+++ b/ElementX/Sources/Services/ElementCall/ElementCallService.swift
@@ -103,6 +103,17 @@ class ElementCallService: NSObject, ElementCallServiceProtocol, PKPushRegistryDe
         } catch {
             MXLog.error("Failed requesting start call action with error: \(error)")
         }
+        
+        do {
+            // Have ElementCall default to the speaker so that the lock button doesn't end the call.
+            // Could also use `overrideOutputAudioPort` but the documentation is clear about it:
+            // `Sessions using PlayAndRecord category that always want to prefer the built-in
+            // speaker output over the receiver, should use AVAudioSessionCategoryOptionDefaultToSpeaker instead.`.
+            try AVAudioSession.sharedInstance().setCategory(.playAndRecord, mode: .videoChat, options: [.defaultToSpeaker])
+            try AVAudioSession.sharedInstance().setActive(true, options: .notifyOthersOnDeactivation)
+        } catch {
+            MXLog.error("Failed setting up audio session with error: \(error)")
+        }
     }
     
     func tearDownCallSession() {