diff --git a/test/testsupport/ivf_video_frame_generator.cc b/test/testsupport/ivf_video_frame_generator.cc
index 47edfaa357..9fb057f1c9 100644
--- a/test/testsupport/ivf_video_frame_generator.cc
+++ b/test/testsupport/ivf_video_frame_generator.cc
@@ -45,10 +45,9 @@ IvfVideoFrameGenerator::IvfVideoFrameGenerator(const std::string& file_name)
   RTC_CHECK_EQ(
       video_decoder_->InitDecode(&codec_settings, /*number_of_cores=*/1),
       WEBRTC_VIDEO_CODEC_OK);
-  sequence_checker_.Detach();
 }
 IvfVideoFrameGenerator::~IvfVideoFrameGenerator() {
-  RTC_DCHECK_RUN_ON(&sequence_checker_);
+  rtc::CritScope crit(&lock_);
   if (!file_reader_) {
     return;
   }
@@ -57,7 +56,7 @@ IvfVideoFrameGenerator::~IvfVideoFrameGenerator() {
   // Reset decoder to prevent it from async access to |this|.
   video_decoder_.reset();
   {
-    rtc::CritScope crit(&lock_);
+    rtc::CritScope frame_crit(&frame_decode_lock_);
     next_frame_ = absl::nullopt;
     // Set event in case another thread is waiting on it.
     next_frame_decoded_.Set();
@@ -65,7 +64,7 @@ IvfVideoFrameGenerator::~IvfVideoFrameGenerator() {
 }
 
 FrameGeneratorInterface::VideoFrameData IvfVideoFrameGenerator::NextFrame() {
-  RTC_DCHECK_RUN_ON(&sequence_checker_);
+  rtc::CritScope crit(&lock_);
   next_frame_decoded_.Reset();
   RTC_CHECK(file_reader_);
   if (!file_reader_->HasMoreFrames()) {
@@ -81,7 +80,7 @@ FrameGeneratorInterface::VideoFrameData IvfVideoFrameGenerator::NextFrame() {
   RTC_CHECK(decoded) << "Failed to decode next frame in "
                      << kMaxNextFrameWaitTemeoutMs << "ms. Can't continue";
 
-  rtc::CritScope crit(&lock_);
+  rtc::CritScope frame_crit(&frame_decode_lock_);
   rtc::scoped_refptr<VideoFrameBuffer> buffer =
       next_frame_->video_frame_buffer();
   if (width_ != static_cast<size_t>(buffer->width()) ||
@@ -97,7 +96,7 @@ FrameGeneratorInterface::VideoFrameData IvfVideoFrameGenerator::NextFrame() {
 }
 
 void IvfVideoFrameGenerator::ChangeResolution(size_t width, size_t height) {
-  RTC_DCHECK_RUN_ON(&sequence_checker_);
+  rtc::CritScope crit(&lock_);
   width_ = width;
   height_ = height;
 }
@@ -121,7 +120,7 @@ void IvfVideoFrameGenerator::DecodedCallback::Decoded(
 }
 
 void IvfVideoFrameGenerator::OnFrameDecoded(const VideoFrame& decoded_frame) {
-  rtc::CritScope crit(&lock_);
+  rtc::CritScope crit(&frame_decode_lock_);
   next_frame_ = decoded_frame;
   next_frame_decoded_.Set();
 }
diff --git a/test/testsupport/ivf_video_frame_generator.h b/test/testsupport/ivf_video_frame_generator.h
index e193a039c8..913d882766 100644
--- a/test/testsupport/ivf_video_frame_generator.h
+++ b/test/testsupport/ivf_video_frame_generator.h
@@ -63,11 +63,22 @@ class IvfVideoFrameGenerator : public FrameGeneratorInterface {
   size_t width_;
   size_t height_;
 
-  rtc::Event next_frame_decoded_;
-  SequenceChecker sequence_checker_;
-
+  // This lock is used to ensure that all API method will be called
+  // sequentially. It is required because we need to ensure that generator
+  // won't be destroyed while it is reading the next frame on another thread,
+  // because it will cause SIGSEGV when decoder callback will be invoked.
+  //
+  // FrameGenerator is injected into PeerConnection via some scoped_ref object
+  // and it can happen that the last pointer will be destroyed on the different
+  // thread comparing to the one from which frames were read.
   rtc::CriticalSection lock_;
-  absl::optional<VideoFrame> next_frame_ RTC_GUARDED_BY(lock_);
+  // This lock is used to sync between sending and receiving frame from decoder.
+  // We can't reuse |lock_| because then generator can be destroyed between
+  // frame was sent to decoder and decoder callback was invoked.
+  rtc::CriticalSection frame_decode_lock_;
+
+  rtc::Event next_frame_decoded_;
+  absl::optional<VideoFrame> next_frame_ RTC_GUARDED_BY(frame_decode_lock_);
 };
 
 }  // namespace test