diff --git a/Sources/PlayerBridge.swift b/Sources/PlayerBridge.swift
index 180982a..842a239 100644
--- a/Sources/PlayerBridge.swift
+++ b/Sources/PlayerBridge.swift
@@ -215,11 +215,13 @@ final class PlayerBridge: ObservableObject {
     
     // MARK: - 播放结束
     private func setupEndObserver() {
-        // queue: .main → 回调已在主线程，直接调用，不创建 Task
         endObserverToken = NotificationCenter.default.addObserver(
             forName: .AVPlayerItemDidPlayToEndTime, object: nil, queue: .main
-        ) { [weak self] _ in
+        ) { [weak self] notification in
             guard let self = self else { return }
+            // 只处理当前 item 的结束通知，忽略旧 item 被替换时发出的残留通知
+            guard let endedItem = notification.object as? AVPlayerItem,
+                  endedItem === self.player.currentItem else { return }
             Task { @MainActor in self.onPlaybackEnded() }
         }
     }
diff --git a/Sources/PlayerRecorder.swift b/Sources/PlayerRecorder.swift
index 7733f04..fd29f13 100644
--- a/Sources/PlayerRecorder.swift
+++ b/Sources/PlayerRecorder.swift
@@ -284,16 +284,17 @@ struct AudioDiagStats {
 final class PlayerRecorder: NSObject {
     
     private var writer: AVAssetWriter?
-    private var videoInput: AVAssetWriterInput?
+    nonisolated(unsafe) private var videoInput: AVAssetWriterInput?
     private var audioInput: AVAssetWriterInput?
-    private var captureTimer: Timer?
+    private var captureTimer: DispatchSourceTimer?
+    private let captureQueue = DispatchQueue(label: "miniplayer.videoCapture", qos: .userInteractive)
     private var durationTimer: Timer?
     private var startDate: Date?
-    private weak var weakOutput: AVPlayerItemVideoOutput?
+    nonisolated(unsafe) private weak var weakOutput: AVPlayerItemVideoOutput?
     nonisolated(unsafe) private var isRunning = false
     
-    private var lastPixelBuffer: CVPixelBuffer?
-    private var captureFrameCount: Int = 0
+    nonisolated(unsafe) private var lastPixelBuffer: CVPixelBuffer?
+    nonisolated(unsafe) private var captureFrameCount: Int = 0
     
     // Audio Tap
     private var tapContext: AudioTapContext?
@@ -556,7 +557,7 @@ final class PlayerRecorder: NSObject {
         isRecording = false
         isRunning = false
         RecorderState.isFinalizing = true
-        captureTimer?.invalidate()
+        captureTimer?.cancel()
         captureTimer = nil
         stopDurationTimer()
         
@@ -667,17 +668,19 @@ final class PlayerRecorder: NSObject {
         lastPixelBuffer = nil
     }
 
-    // MARK: - 视频抓帧 (30fps Timer)
+    // MARK: - 视频抓帧 (30fps, 独立队列避免阻塞主线程渲染)
     
     private func startCaptureLoop() {
-        captureTimer = Timer.scheduledTimer(withTimeInterval: 1.0 / 30.0, repeats: true) { [weak self] _ in
-            Task { @MainActor in
-                self?.captureVideoFrame()
-            }
+        let timer = DispatchSource.makeTimerSource(queue: captureQueue)
+        timer.schedule(deadline: .now(), repeating: .milliseconds(33), leeway: .milliseconds(2))
+        timer.setEventHandler { [weak self] in
+            self?.captureVideoFrame()
         }
+        timer.resume()
+        captureTimer = timer
     }
     
-    private func captureVideoFrame() {
+    nonisolated private func captureVideoFrame() {
         guard isRunning, let output = weakOutput, let input = videoInput,
               input.isReadyForMoreMediaData else { return }
         
@@ -700,7 +703,7 @@ final class PlayerRecorder: NSObject {
         }
     }
     
-    private static func createSampleBuffer(from pixelBuffer: CVPixelBuffer, time: CMTime) -> CMSampleBuffer? {
+    nonisolated private static func createSampleBuffer(from pixelBuffer: CVPixelBuffer, time: CMTime) -> CMSampleBuffer? {
         var info = CMSampleTimingInfo()
         info.presentationTimeStamp = time
         info.duration = CMTime(value: 1, timescale: 30)