diff --git a/api/frame_transformer_factory.cc b/api/frame_transformer_factory.cc
index 262ac0795c..841ab0f941 100644
--- a/api/frame_transformer_factory.cc
+++ b/api/frame_transformer_factory.cc
@@ -25,7 +25,7 @@ std::unique_ptr<TransformableVideoFrameInterface> CreateVideoReceiverFrame() {
   return nullptr;
 }
 
-std::unique_ptr<TransformableFrameInterface> CloneAudioFrame(
+std::unique_ptr<TransformableAudioFrameInterface> CloneAudioFrame(
     TransformableAudioFrameInterface* original) {
   // At the moment, only making sender frames is supported.
   return CloneSenderAudioFrame(original);
diff --git a/api/frame_transformer_factory.h b/api/frame_transformer_factory.h
index e0a7bdf4af..a73ff62956 100644
--- a/api/frame_transformer_factory.h
+++ b/api/frame_transformer_factory.h
@@ -32,7 +32,7 @@ std::unique_ptr<TransformableVideoFrameInterface> CreateVideoSenderFrame();
 std::unique_ptr<TransformableVideoFrameInterface> CreateVideoReceiverFrame();
 // Creates a new frame with the same metadata as the original.
 // The original can be a sender or receiver frame.
-RTC_EXPORT std::unique_ptr<TransformableFrameInterface> CloneAudioFrame(
+RTC_EXPORT std::unique_ptr<TransformableAudioFrameInterface> CloneAudioFrame(
     TransformableAudioFrameInterface* original);
 RTC_EXPORT std::unique_ptr<TransformableVideoFrameInterface> CloneVideoFrame(
     TransformableVideoFrameInterface* original);
diff --git a/api/frame_transformer_interface.h b/api/frame_transformer_interface.h
index d4b09a46e2..c47bad4243 100644
--- a/api/frame_transformer_interface.h
+++ b/api/frame_transformer_interface.h
@@ -72,9 +72,17 @@ class TransformableAudioFrameInterface : public TransformableFrameInterface {
   // Exposes the frame header, enabling the interface clients to use the
   // information in the header as needed, for example to compile the list of
   // csrcs.
+  // TODO(crbug.com/1453226): Deprecate and remove once callers have migrated to
+  // the getters for specific fields.
   virtual const RTPHeader& GetHeader() const = 0;
 
   virtual rtc::ArrayView<const uint32_t> GetContributingSources() const = 0;
+
+  // TODO(crbug.com/1453226): Change this to pure virtual after it
+  // is implemented everywhere.
+  virtual const absl::optional<uint16_t> SequenceNumber() const {
+    return absl::nullopt;
+  }
 };
 
 // Objects implement this interface to be notified with the transformed frame.
diff --git a/api/test/mock_transformable_audio_frame.h b/api/test/mock_transformable_audio_frame.h
index 912488adbc..9b52e5c579 100644
--- a/api/test/mock_transformable_audio_frame.h
+++ b/api/test/mock_transformable_audio_frame.h
@@ -29,6 +29,14 @@ class MockTransformableAudioFrame : public TransformableAudioFrameInterface {
               GetContributingSources,
               (),
               (const override));
+  MOCK_METHOD(const absl::optional<uint16_t>,
+              SequenceNumber,
+              (),
+              (const, override));
+  MOCK_METHOD(TransformableFrameInterface::Direction,
+              GetDirection,
+              (),
+              (const, override));
 };
 
 }  // namespace webrtc
diff --git a/audio/channel_receive_frame_transformer_delegate.cc b/audio/channel_receive_frame_transformer_delegate.cc
index 1cb08f0680..8f817c6fe7 100644
--- a/audio/channel_receive_frame_transformer_delegate.cc
+++ b/audio/channel_receive_frame_transformer_delegate.cc
@@ -46,6 +46,10 @@ class TransformableIncomingAudioFrame
   }
   Direction GetDirection() const override { return Direction::kReceiver; }
 
+  const absl::optional<uint16_t> SequenceNumber() const override {
+    return header_.sequenceNumber;
+  }
+
  private:
   rtc::Buffer payload_;
   RTPHeader header_;
diff --git a/audio/channel_send_frame_transformer_delegate.cc b/audio/channel_send_frame_transformer_delegate.cc
index bf7b49527c..93aaa4324d 100644
--- a/audio/channel_send_frame_transformer_delegate.cc
+++ b/audio/channel_send_frame_transformer_delegate.cc
@@ -15,7 +15,8 @@
 namespace webrtc {
 namespace {
 
-class TransformableOutgoingAudioFrame : public TransformableFrameInterface {
+class TransformableOutgoingAudioFrame
+    : public TransformableAudioFrameInterface {
  public:
   TransformableOutgoingAudioFrame(AudioFrameType frame_type,
                                   uint8_t payload_type,
@@ -50,6 +51,22 @@ class TransformableOutgoingAudioFrame : public TransformableFrameInterface {
   }
   Direction GetDirection() const override { return Direction::kSender; }
 
+  // TODO(crbug.com/1453226): Remove once GetHeader() is removed from
+  // TransformableAudioFrameInterface.
+  const RTPHeader& GetHeader() const override { return empty_header_; }
+
+  rtc::ArrayView<const uint32_t> GetContributingSources() const override {
+    return {};
+  }
+
+  const absl::optional<uint16_t> SequenceNumber() const override {
+    return absl::nullopt;
+  }
+
+  void SetRTPTimestamp(uint32_t timestamp) override {
+    rtp_timestamp_ = timestamp - rtp_start_timestamp_;
+  }
+
  private:
   AudioFrameType frame_type_;
   uint8_t payload_type_;
@@ -58,6 +75,10 @@ class TransformableOutgoingAudioFrame : public TransformableFrameInterface {
   rtc::Buffer payload_;
   int64_t absolute_capture_timestamp_ms_;
   uint32_t ssrc_;
+
+  // TODO(crbug.com/1453226): Remove once GetHeader() is removed from
+  // TransformableAudioFrameInterface.
+  RTPHeader empty_header_;
 };
 }  // namespace
 
@@ -127,7 +148,7 @@ void ChannelSendFrameTransformerDelegate::SendFrame(
                        transformed_frame->GetAbsoluteCaptureTimestampMs());
 }
 
-std::unique_ptr<TransformableFrameInterface> CloneSenderAudioFrame(
+std::unique_ptr<TransformableAudioFrameInterface> CloneSenderAudioFrame(
     TransformableAudioFrameInterface* original) {
   AudioFrameType audio_frame_type =
       original->GetHeader().extension.voiceActivity
diff --git a/audio/channel_send_frame_transformer_delegate.h b/audio/channel_send_frame_transformer_delegate.h
index 6bd0af70d7..c866638547 100644
--- a/audio/channel_send_frame_transformer_delegate.h
+++ b/audio/channel_send_frame_transformer_delegate.h
@@ -78,7 +78,7 @@ class ChannelSendFrameTransformerDelegate : public TransformedFrameCallback {
   rtc::TaskQueue* encoder_queue_ RTC_GUARDED_BY(send_lock_);
 };
 
-std::unique_ptr<TransformableFrameInterface> CloneSenderAudioFrame(
+std::unique_ptr<TransformableAudioFrameInterface> CloneSenderAudioFrame(
     TransformableAudioFrameInterface* original);
 
 }  // namespace webrtc