diff --git a/media/engine/webrtc_voice_engine.cc b/media/engine/webrtc_voice_engine.cc
index cbc6abf..0cf17ed 100644
--- a/media/engine/webrtc_voice_engine.cc
+++ b/media/engine/webrtc_voice_engine.cc
@@ -210,6 +210,11 @@
   return absl::StartsWith(config.Lookup(trial), "Enabled");
 }
 
+bool IsDisabled(const webrtc::WebRtcKeyValueConfig& config,
+                absl::string_view trial) {
+  return absl::StartsWith(config.Lookup(trial), "Disabled");
+}
+
 struct AdaptivePtimeConfig {
   bool enabled = false;
   webrtc::DataRate min_payload_bitrate = webrtc::DataRate::KilobitsPerSec(16);
@@ -304,8 +309,8 @@
       audio_mixer_(audio_mixer),
       apm_(audio_processing),
       audio_frame_processor_(audio_frame_processor),
-      audio_red_for_opus_trial_enabled_(
-          IsEnabled(trials, "WebRTC-Audio-Red-For-Opus")),
+      audio_red_for_opus_enabled_(
+          !IsDisabled(trials, "WebRTC-Audio-Red-For-Opus")),
       minimized_remsampling_on_mobile_trial_enabled_(
           IsEnabled(trials, "WebRTC-Audio-MinimizeResamplingOnMobile")) {
   // This may be called from any thread, so detach thread checkers.
@@ -769,7 +774,7 @@
 
       out.push_back(codec);
 
-      if (codec.name == kOpusCodecName && audio_red_for_opus_trial_enabled_) {
+      if (codec.name == kOpusCodecName && audio_red_for_opus_enabled_) {
         map_format({kRedCodecName, 48000, 2}, &out);
       }
     }
@@ -1336,8 +1341,8 @@
       call_(call),
       audio_config_(config.audio),
       crypto_options_(crypto_options),
-      audio_red_for_opus_trial_enabled_(
-          IsEnabled(call->trials(), "WebRTC-Audio-Red-For-Opus")) {
+      audio_red_for_opus_enabled_(
+          !IsDisabled(call->trials(), "WebRTC-Audio-Red-For-Opus")) {
   network_thread_checker_.Detach();
   RTC_LOG(LS_VERBOSE) << "WebRtcVoiceMediaChannel::WebRtcVoiceMediaChannel";
   RTC_DCHECK(call);
@@ -1598,8 +1603,7 @@
     }
     auto format = AudioCodecToSdpAudioFormat(codec);
     if (!IsCodec(codec, kCnCodecName) && !IsCodec(codec, kDtmfCodecName) &&
-        (!audio_red_for_opus_trial_enabled_ ||
-         !IsCodec(codec, kRedCodecName)) &&
+        (!audio_red_for_opus_enabled_ || !IsCodec(codec, kRedCodecName)) &&
         !engine()->decoder_factory_->IsSupportedDecoder(format)) {
       RTC_LOG(LS_ERROR) << "Unsupported codec: " << rtc::ToString(format);
       return false;
@@ -1753,7 +1757,7 @@
     }
   }
 
-  if (audio_red_for_opus_trial_enabled_) {
+  if (audio_red_for_opus_enabled_) {
     // Loop through the codecs to find the RED codec that matches opus
     // with respect to clockrate and number of channels.
     size_t red_codec_position = 0;
diff --git a/media/engine/webrtc_voice_engine.h b/media/engine/webrtc_voice_engine.h
index 147688b..a7c2f39 100644
--- a/media/engine/webrtc_voice_engine.h
+++ b/media/engine/webrtc_voice_engine.h
@@ -133,9 +133,9 @@
   int audio_jitter_buffer_min_delay_ms_ = 0;
   bool audio_jitter_buffer_enable_rtx_handling_ = false;
 
-  // If this field trial is enabled, we will negotiate and use RFC 2198
+  // If this field is enabled, we will negotiate and use RFC 2198
   // redundancy for opus audio.
-  const bool audio_red_for_opus_trial_enabled_;
+  const bool audio_red_for_opus_enabled_;
   const bool minimized_remsampling_on_mobile_trial_enabled_;
 };
 
@@ -328,7 +328,7 @@
   rtc::scoped_refptr<webrtc::FrameDecryptorInterface>
       unsignaled_frame_decryptor_;
 
-  const bool audio_red_for_opus_trial_enabled_;
+  const bool audio_red_for_opus_enabled_;
 };
 }  // namespace cricket
 
diff --git a/media/engine/webrtc_voice_engine_unittest.cc b/media/engine/webrtc_voice_engine_unittest.cc
index 1fd2480..4b127af 100644
--- a/media/engine/webrtc_voice_engine_unittest.cc
+++ b/media/engine/webrtc_voice_engine_unittest.cc
@@ -1022,11 +1022,8 @@
   EXPECT_TRUE(channel_->SetRecvParameters(parameters));
 }
 
-// Test that we set Opus/Red under the field trial.
-TEST_P(WebRtcVoiceEngineTestFake, RecvRed) {
-  webrtc::test::ScopedFieldTrials override_field_trials(
-      "WebRTC-Audio-Red-For-Opus/Enabled/");
-
+// Test that we do allow setting Opus/Red by default.
+TEST_P(WebRtcVoiceEngineTestFake, RecvRedDefault) {
   EXPECT_TRUE(SetupRecvStream());
   cricket::AudioRecvParameters parameters;
   parameters.codecs.push_back(kOpusCodec);
@@ -1037,8 +1034,11 @@
                   {{111, {"opus", 48000, 2}}, {112, {"red", 48000, 2}}})));
 }
 
-// Test that we do not allow setting Opus/Red by default.
-TEST_P(WebRtcVoiceEngineTestFake, RecvRedDefault) {
+// Test that we disable Opus/Red with the kill switch.
+TEST_P(WebRtcVoiceEngineTestFake, RecvRed) {
+  webrtc::test::ScopedFieldTrials override_field_trials(
+      "WebRTC-Audio-Red-For-Opus/Disabled/");
+
   EXPECT_TRUE(SetupRecvStream());
   cricket::AudioRecvParameters parameters;
   parameters.codecs.push_back(kOpusCodec);