diff --git a/tools/cabana/streams/abstractstream.cc b/tools/cabana/streams/abstractstream.cc
index ad911b7baedcf7..2278104c269171 100644
--- a/tools/cabana/streams/abstractstream.cc
+++ b/tools/cabana/streams/abstractstream.cc
@@ -143,7 +143,6 @@ bool AbstractStream::isMessageActive(const MessageId &id) const {
 }
 
 void AbstractStream::updateLastMsgsTo(double sec) {
-  std::lock_guard lk(mutex_);
   current_sec_ = sec;
   uint64_t last_ts = toMonoTime(sec);
   std::unordered_map<MessageId, CanData> msgs;
@@ -175,10 +174,17 @@ void AbstractStream::updateLastMsgsTo(double sec) {
                     std::any_of(messages_.cbegin(), messages_.cend(),
                                 [this](const auto &m) { return !last_msgs.count(m.first); });
   last_msgs = messages_;
-  mutex_.unlock();
-
   emit msgsReceived(nullptr, id_changed);
-  resumeStream();
+
+  std::lock_guard lk(mutex_);
+  seek_finished_ = true;
+  seek_finished_cv_.notify_one();
+}
+
+void AbstractStream::waitForSeekFinshed() {
+  std::unique_lock lock(mutex_);
+  seek_finished_cv_.wait(lock, [this]() { return seek_finished_; });
+  seek_finished_ = false;
 }
 
 const CanEvent *AbstractStream::newEvent(uint64_t mono_time, const cereal::CanData::Reader &c) {
diff --git a/tools/cabana/streams/abstractstream.h b/tools/cabana/streams/abstractstream.h
index 8180c6b6f8b72b..f35b19d34f7045 100644
--- a/tools/cabana/streams/abstractstream.h
+++ b/tools/cabana/streams/abstractstream.h
@@ -2,6 +2,7 @@
 
 #include <algorithm>
 #include <array>
+#include <condition_variable>
 #include <memory>
 #include <mutex>
 #include <optional>
@@ -111,7 +112,7 @@ class AbstractStream : public QObject {
   void mergeEvents(const std::vector<const CanEvent *> &events);
   const CanEvent *newEvent(uint64_t mono_time, const cereal::CanData::Reader &c);
   void updateEvent(const MessageId &id, double sec, const uint8_t *data, uint8_t size);
-  virtual void resumeStream() {}
+  void waitForSeekFinshed();
   std::vector<const CanEvent *> all_events_;
   double current_sec_ = 0;
   std::optional<std::pair<double, double>> time_range_;
@@ -127,6 +128,8 @@ class AbstractStream : public QObject {
 
   // Members accessed in multiple threads. (mutex protected)
   std::mutex mutex_;
+  std::condition_variable seek_finished_cv_;
+  bool seek_finished_ = false;
   std::set<MessageId> new_msgs_;
   std::unordered_map<MessageId, CanData> messages_;
   std::unordered_map<MessageId, std::vector<uint8_t>> masks_;
diff --git a/tools/cabana/streams/replaystream.cc b/tools/cabana/streams/replaystream.cc
index bfe5ca74da1580..ebe478ded77d1d 100644
--- a/tools/cabana/streams/replaystream.cc
+++ b/tools/cabana/streams/replaystream.cc
@@ -53,9 +53,12 @@ bool ReplayStream::loadRoute(const QString &route, const QString &data_dir, uint
 
   // Forward replay callbacks to corresponding Qt signals.
   replay->onSeeking = [this](double sec) { emit seeking(sec); };
-  replay->onSeekedTo = [this](double sec) { emit seekedTo(sec); };
+  replay->onSeekedTo = [this](double sec) {
+    emit seekedTo(sec);
+    waitForSeekFinshed();
+  };
   replay->onQLogLoaded = [this](std::shared_ptr<LogReader> qlog) { emit qLogLoaded(qlog); };
-  replay->onSegmentsMerged = [this]() { QMetaObject::invokeMethod(this, &ReplayStream::mergeSegments, Qt::QueuedConnection); };
+  replay->onSegmentsMerged = [this]() { QMetaObject::invokeMethod(this, &ReplayStream::mergeSegments, Qt::BlockingQueuedConnection); };
 
   bool success = replay->load();
   if (!success) {
diff --git a/tools/cabana/streams/replaystream.h b/tools/cabana/streams/replaystream.h
index 2d7f3351935d9c..df1f2526a5e328 100644
--- a/tools/cabana/streams/replaystream.h
+++ b/tools/cabana/streams/replaystream.h
@@ -32,7 +32,6 @@ class ReplayStream : public AbstractStream {
   inline float getSpeed() const { return replay->getSpeed(); }
   inline Replay *getReplay() const { return replay.get(); }
   inline bool isPaused() const override { return replay->isPaused(); }
-  void resumeStream() override { return replay->resumeStream(); }
   void pause(bool pause) override;
 
 signals:
diff --git a/tools/replay/replay.cc b/tools/replay/replay.cc
index 2bd3614530abae..a940b6d04e81a8 100644
--- a/tools/replay/replay.cc
+++ b/tools/replay/replay.cc
@@ -106,31 +106,27 @@ void Replay::seekTo(double seconds, bool relative) {
   rInfo("Seeking to %d s, segment %d", (int)target_time, target_segment);
   notifyEvent(onSeeking, target_time);
 
-  double seeked_to_sec = -1;
   interruptStream([&]() {
-    current_segment_ = target_segment;
+    current_segment_.store(target_segment);
     cur_mono_time_ = route_start_ts_ + target_time * 1e9;
-    seeking_to_ = target_time;
-
-    if (event_data_->isSegmentLoaded(target_segment)) {
-      seeked_to_sec = *seeking_to_;
-      seeking_to_.reset();
-    }
+    seeking_to_.store(target_time, std::memory_order_relaxed);
     return false;
   });
 
-  checkSeekProgress(seeked_to_sec);
   seg_mgr_->setCurrentSegment(target_segment);
+  checkSeekProgress();
 }
 
-void Replay::checkSeekProgress(double seeked_to_sec) {
-  if (seeked_to_sec >= 0) {
-    if (onSeekedTo) {
-      onSeekedTo(seeked_to_sec);
-    } else {
-      interruptStream([]() { return true; });
-    }
+void Replay::checkSeekProgress() {
+  if (!seg_mgr_->getEventData()->isSegmentLoaded(current_segment_.load())) return;
+
+  double seek_to = seeking_to_.exchange(-1.0, std::memory_order_acquire);
+  if (seek_to >= 0 && onSeekedTo) {
+    onSeekedTo(seek_to);
   }
+
+  // Resume the interrupted stream
+  interruptStream([]() { return true; });
 }
 
 void Replay::seekToFlag(FindFlag flag) {
@@ -152,29 +148,19 @@ void Replay::pause(bool pause) {
 void Replay::handleSegmentMerge() {
   if (exit_) return;
 
-  double seeked_to_sec = -1;
-  interruptStream([&]() {
-    event_data_ = seg_mgr_->getEventData();
-    notifyEvent(onSegmentsMerged);
-
-    bool segment_loaded = event_data_->isSegmentLoaded(current_segment_);
-    if (seeking_to_ && segment_loaded) {
-      seeked_to_sec = *seeking_to_;
-      seeking_to_.reset();
-      return false;
-    }
-    return segment_loaded;
-  });
-
-  checkSeekProgress(seeked_to_sec);
-  if (!stream_thread_.joinable() && !event_data_->events.empty()) {
-    startStream();
+  auto event_data = seg_mgr_->getEventData();
+  if (!stream_thread_.joinable() && !event_data->segments.empty()) {
+    startStream(event_data->segments.begin()->second);
   }
+  notifyEvent(onSegmentsMerged);
+
+  // Interrupt the stream to handle segment merge
+  interruptStream([]() { return false; });
+  checkSeekProgress();
 }
 
-void Replay::startStream() {
-  const auto &cur_segment = event_data_->segments.begin()->second;
-  const auto &events = cur_segment->log->events;
+void Replay::startStream(const std::shared_ptr<Segment> segment) {
+  const auto &events = segment->log->events;
   route_start_ts_ = events.front().mono_time;
   cur_mono_time_ += route_start_ts_ - 1;
 
@@ -212,7 +198,7 @@ void Replay::startStream() {
   if (!hasFlag(REPLAY_FLAG_NO_VIPC)) {
     std::pair<int, int> camera_size[MAX_CAMERAS] = {};
     for (auto type : ALL_CAMERAS) {
-      if (auto &fr = cur_segment->frames[type]) {
+      if (auto &fr = segment->frames[type]) {
         camera_size[type] = {fr->width, fr->height};
       }
     }
@@ -271,6 +257,7 @@ void Replay::streamThread() {
     stream_cv_.wait(lk, [this]() { return exit_ || (events_ready_ && !interrupt_requested_); });
     if (exit_) break;
 
+    event_data_ = seg_mgr_->getEventData();
     const auto &events = event_data_->events;
     auto first = std::upper_bound(events.cbegin(), events.cend(), Event(cur_which, cur_mono_time_, {}));
     if (first == events.cend()) {
@@ -308,11 +295,11 @@ std::vector<Event>::const_iterator Replay::publishEvents(std::vector<Event>::con
 
   for (; !interrupt_requested_ && first != last; ++first) {
     const Event &evt = *first;
-    int segment = toSeconds(evt.mono_time) / 60;
 
-    if (current_segment_ != segment) {
-      current_segment_ = segment;
-      seg_mgr_->setCurrentSegment(current_segment_);
+    int segment = toSeconds(evt.mono_time) / 60;
+    if (current_segment_.load(std::memory_order_relaxed) != segment) {
+      current_segment_.store(segment, std::memory_order_relaxed);
+      seg_mgr_->setCurrentSegment(segment);
     }
 
     // Skip events if socket is not present
diff --git a/tools/replay/replay.h b/tools/replay/replay.h
index d549eaefc4dd76..8525a532a1766c 100644
--- a/tools/replay/replay.h
+++ b/tools/replay/replay.h
@@ -55,9 +55,8 @@ class Replay {
   inline const std::string &carFingerprint() const { return car_fingerprint_; }
   inline const std::shared_ptr<std::vector<Timeline::Entry>> getTimeline() const { return timeline_.getEntries(); }
   inline const std::optional<Timeline::Entry> findAlertAtTime(double sec) const { return timeline_.findAlertAtTime(sec); }
-  const std::shared_ptr<SegmentManager::EventData> getEventData() const { return event_data_; }
+  const std::shared_ptr<SegmentManager::EventData> getEventData() const { return seg_mgr_->getEventData(); }
   void installEventFilter(std::function<bool(const Event *)> filter) { event_filter_ = filter; }
-  void resumeStream() { interruptStream([]() { return true; }); }
 
   // Event callback functions
   std::function<void()> onSegmentsMerged = nullptr;
@@ -68,7 +67,7 @@ class Replay {
 private:
   void setupServices(const std::vector<std::string> &allow, const std::vector<std::string> &block);
   void setupSegmentManager(bool has_filters);
-  void startStream();
+  void startStream(const std::shared_ptr<Segment> segment);
   void streamThread();
   void handleSegmentMerge();
   void interruptStream(const std::function<bool()>& update_fn);
@@ -76,7 +75,7 @@ class Replay {
                                                    std::vector<Event>::const_iterator last);
   void publishMessage(const Event *e);
   void publishFrame(const Event *e);
-  void checkSeekProgress(double seeked_to_sec);
+  void checkSeekProgress();
 
   std::unique_ptr<SegmentManager> seg_mgr_;
   Timeline timeline_;
@@ -86,8 +85,8 @@ class Replay {
   std::mutex stream_lock_;
   bool user_paused_ = false;
   std::condition_variable stream_cv_;
-  int current_segment_ = 0;
-  std::optional<double> seeking_to_;
+  std::atomic<int> current_segment_ = 0;
+  std::atomic<double> seeking_to_ = -1.0;
   std::atomic<bool> exit_ = false;
   std::atomic<bool> interrupt_requested_ = false;
   bool events_ready_ = false;
diff --git a/tools/replay/seg_mgr.cc b/tools/replay/seg_mgr.cc
index 954b25e8744f88..8a00d426b1a804 100644
--- a/tools/replay/seg_mgr.cc
+++ b/tools/replay/seg_mgr.cc
@@ -105,7 +105,7 @@ bool SegmentManager::mergeSegments(const SegmentMap::iterator &begin, const Segm
     merged_event_data->segments[n] = segments_.at(n);
   }
 
-  event_data_ = merged_event_data;
+  std::atomic_store(&event_data_, std::move(merged_event_data));
   merged_segments_ = segments_to_merge;
 
   return true;
diff --git a/tools/replay/seg_mgr.h b/tools/replay/seg_mgr.h
index efb3d7f0eadacf..40bdcd51f06d1d 100644
--- a/tools/replay/seg_mgr.h
+++ b/tools/replay/seg_mgr.h
@@ -21,14 +21,14 @@ class SegmentManager {
   };
 
   SegmentManager(const std::string &route_name, uint32_t flags, const std::string &data_dir = "")
-      : flags_(flags), route_(route_name, data_dir) {};
+      : flags_(flags), route_(route_name, data_dir), event_data_(std::make_shared<EventData>()) {}
   ~SegmentManager();
 
   bool load();
   void setCurrentSegment(int seg_num);
   void setCallback(const std::function<void()> &callback) { onSegmentMergedCallback_ = callback; }
   void setFilters(const std::vector<bool> &filters) { filters_ = filters; }
-  const std::shared_ptr<EventData> getEventData() const { return event_data_; }
+  const std::shared_ptr<EventData> getEventData() const { return std::atomic_load(&event_data_); }
   bool hasSegment(int n) const { return segments_.find(n) != segments_.end(); }
 
   Route route_;
diff --git a/tools/replay/timeline.cc b/tools/replay/timeline.cc
index d836de972b60f0..a4c2ffb700c1a4 100644
--- a/tools/replay/timeline.cc
+++ b/tools/replay/timeline.cc
@@ -1,7 +1,7 @@
 #include "tools/replay/timeline.h"
 
-#include <array>
 #include <algorithm>
+#include <array>
 
 #include "cereal/gen/cpp/log.capnp.h"
 
@@ -74,7 +74,7 @@ void Timeline::buildTimeline(const Route &route, uint64_t route_start_ts, bool l
     // Sort and finalize the timeline entries
     auto entries = std::make_shared<std::vector<Entry>>(staging_entries_);
     std::sort(entries->begin(), entries->end(), [](auto &a, auto &b) { return a.start_time < b.start_time; });
-    timeline_entries_ = entries;
+    std::atomic_store(&timeline_entries_, std::move(entries));
 
     callback(log);  // Notify the callback once the log is processed
   }
diff --git a/tools/replay/timeline.h b/tools/replay/timeline.h
index 689a80635f9b0d..74add9e5cc4623 100644
--- a/tools/replay/timeline.h
+++ b/tools/replay/timeline.h
@@ -27,20 +27,20 @@ class Timeline {
                   std::function<void(std::shared_ptr<LogReader>)> callback);
   std::optional<uint64_t> find(double cur_ts, FindFlag flag) const;
   std::optional<Entry> findAlertAtTime(double target_time) const;
-  const std::shared_ptr<std::vector<Entry>> getEntries() const { return timeline_entries_; }
+  const std::shared_ptr<std::vector<Entry>> getEntries() const { return std::atomic_load(&timeline_entries_); }
 
 private:
- void buildTimeline(const Route &route, uint64_t route_start_ts, bool local_cache,
-                    std::function<void(std::shared_ptr<LogReader>)> callback);
- void updateEngagementStatus(const cereal::SelfdriveState::Reader &cs, std::optional<size_t> &idx, double seconds);
- void updateAlertStatus(const cereal::SelfdriveState::Reader &cs, std::optional<size_t> &idx, double seconds);
+  void buildTimeline(const Route &route, uint64_t route_start_ts, bool local_cache,
+                     std::function<void(std::shared_ptr<LogReader>)> callback);
+  void updateEngagementStatus(const cereal::SelfdriveState::Reader &cs, std::optional<size_t> &idx, double seconds);
+  void updateAlertStatus(const cereal::SelfdriveState::Reader &cs, std::optional<size_t> &idx, double seconds);
 
- std::thread thread_;
- std::atomic<bool> should_exit_ = false;
+  std::thread thread_;
+  std::atomic<bool> should_exit_ = false;
 
- // Temporarily holds entries before they are sorted and finalized
- std::vector<Entry> staging_entries_;
+  // Temporarily holds entries before they are sorted and finalized
+  std::vector<Entry> staging_entries_;
 
- // Final sorted timeline entries
- std::shared_ptr<std::vector<Entry>> timeline_entries_;
+  // Final sorted timeline entries
+  std::shared_ptr<std::vector<Entry>> timeline_entries_;
 };