diff --git a/lib/msc_extensions/extension_audio_events/audio_events.dart b/lib/msc_extensions/extension_audio_events/audio_events.dart
index 3d1a735f..f93ef5ec 100644
--- a/lib/msc_extensions/extension_audio_events/audio_events.dart
+++ b/lib/msc_extensions/extension_audio_events/audio_events.dart
@@ -1,19 +1,11 @@
 import 'package:matrix/matrix.dart';
 
-extension AudioEventExtension on Event {
-  /// returns if the event is a voice message
-  bool get isVoiceMessage =>
-      content['org.matrix.msc2516.voice'] is Map<String, Object?> ||
-      content['org.matrix.msc3245.voice'] is Map<String, Object?>;
-}
-
 extension AudioEventRoomExtension on Room {
   /// Sends an audio file with appropriate info to this room. Returns the event
   /// ID generated by the server for this event.
   Future<String?> sendAudioEvent(
     MatrixAudioFile audioFile, {
     Event? replyTo,
-    bool isVoiceMessage = false,
     int? durationInMs,
     List<int>? waveform,
     Map<String, dynamic>? otherFileInfo,
@@ -24,10 +16,6 @@ extension AudioEventRoomExtension on Room {
       otherFileInfo['duration'] = durationInMs;
     }
     if (otherFileInfo != null) extraContent['info'] = otherFileInfo;
-    if (isVoiceMessage) {
-      // No content, this is only used to identify if the event is a voice message.
-      extraContent['org.matrix.msc3245.voice'] = <String, Object?>{};
-    }
     extraContent['org.matrix.msc1767.audio'] = <String, Object?>{
       'duration': durationInMs,
       'waveform': waveform,