diff --git a/apps/web/src/pages/generate/GeneratePage.tsx b/apps/web/src/pages/generate/GeneratePage.tsx
index 29491d027..687e531b4 100644
--- a/apps/web/src/pages/generate/GeneratePage.tsx
+++ b/apps/web/src/pages/generate/GeneratePage.tsx
@@ -107,6 +107,20 @@ const GeneratePage: React.FC = () => {
     [userTemplates, selectedTemplate],
   )
 
+  /* ── 视频总时长计算（用于配音时长校验） ── */
+  const totalVideoDuration = useMemo(() => {
+    if (!previewAssets.length || !currentTemplate) return 0
+    const templateSegments = currentTemplate.segments || []
+    return previewAssets.reduce((sum, asset, i) => {
+      const assetDuration = asset.duration || asset.metadata?.duration || 30
+      const tplSeg = templateSegments[i] || templateSegments[templateSegments.length - 1]
+      const segDuration = tplSeg
+        ? Math.min(tplSeg.duration_max, Math.max(tplSeg.duration_min, assetDuration))
+        : Math.min(assetDuration, 10)
+      return sum + segDuration
+    }, 0)
+  }, [previewAssets, currentTemplate])
+
   /* ── 配音音频 URL ── */
   const { data: voiceMaterials = [] } = useQuery({
     queryKey: ["assets", "voice"],
@@ -207,6 +221,7 @@ const GeneratePage: React.FC = () => {
             duration={duration}
             selectedVoice={selectedVoice}
             onSelectedVoiceChange={setSelectedVoice}
+            totalVideoDuration={totalVideoDuration}
             voiceMode={voiceMode}
             onVoiceModeChange={setVoiceMode}
             selectedClonedVoice={selectedClonedVoice}
diff --git a/apps/web/src/pages/generate/components/FrontendPreviewPlayer.tsx b/apps/web/src/pages/generate/components/FrontendPreviewPlayer.tsx
index 1dd476238..c73b74b22 100644
--- a/apps/web/src/pages/generate/components/FrontendPreviewPlayer.tsx
+++ b/apps/web/src/pages/generate/components/FrontendPreviewPlayer.tsx
@@ -140,7 +140,7 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
     if (!audio || !audio.src || !isPlaying) return
     // 用视频当前的全局时间对齐音频
     audio.currentTime = currentTime
-  }, [currentSegmentIndex])
+  }, [currentSegmentIndex, currentTime, isPlaying])
 
   // seek 时同步音频
   const handleSeekTo = useCallback(
@@ -280,7 +280,8 @@ const FrontendPreviewPlayer: React.FC<FrontendPreviewPlayerProps> = ({
             objectFit: "contain",
             background: "#000",
             zIndex: 1,
-            display: i === currentSegmentIndex ? "block" : "none",
+            opacity: i === currentSegmentIndex ? 1 : 0,
+            pointerEvents: i === currentSegmentIndex ? "auto" : "none",
           }}
           playsInline
         />
diff --git a/apps/web/src/pages/generate/components/GenerateStepContent.tsx b/apps/web/src/pages/generate/components/GenerateStepContent.tsx
index b79a8269d..cac82ca21 100644
--- a/apps/web/src/pages/generate/components/GenerateStepContent.tsx
+++ b/apps/web/src/pages/generate/components/GenerateStepContent.tsx
@@ -54,6 +54,7 @@ export interface GenerateStepContentProps {
   /* 配音 */
   selectedVoice: string
   onSelectedVoiceChange: (id: string) => void
+  totalVideoDuration?: number
   voiceMode: "preset" | "custom" | "clone"
   onVoiceModeChange: (mode: "preset" | "custom" | "clone") => void
   selectedClonedVoice: string
@@ -106,6 +107,7 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
     duration,
     selectedVoice,
     onSelectedVoiceChange,
+    totalVideoDuration,
     voiceMode,
     selectedClonedVoice,
     clonedVoices,
@@ -146,6 +148,7 @@ export const GenerateStepContent: React.FC<GenerateStepContentProps> = (props) =
         <Step3VoiceSelect
           selectedVoice={selectedVoice}
           onSelectedVoiceChange={onSelectedVoiceChange}
+          totalVideoDuration={totalVideoDuration}
         />
       )
     case 4:
diff --git a/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx b/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
index 37d8f5a1d..e5eee7426 100644
--- a/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
+++ b/apps/web/src/pages/generate/components/PreviewVideoPanel.tsx
@@ -143,6 +143,7 @@ const TitleOverlay: React.FC<{ titleSettings: TitleSettings }> = ({ titleSetting
   )
   const titleStyle = useMemo(
     () => buildTitleStyle(titleSettings, containerHeight),
+    // eslint-disable-next-line react-hooks/exhaustive-deps -- 已逐字段列出 titleSettings 依赖
     [
       containerHeight,
       titleSettings.font,
diff --git a/apps/web/src/pages/generate/components/Step5VoiceSelect.tsx b/apps/web/src/pages/generate/components/Step5VoiceSelect.tsx
index 9b56af3df..d799034bf 100644
--- a/apps/web/src/pages/generate/components/Step5VoiceSelect.tsx
+++ b/apps/web/src/pages/generate/components/Step5VoiceSelect.tsx
@@ -5,13 +5,15 @@
 import React, { useState, useRef, useCallback } from "react"
 import { useNavigate } from "react-router-dom"
 import { useQuery } from "@tanstack/react-query"
-import { AudioOutlined, SoundOutlined } from "@ant-design/icons"
+import { AudioOutlined, SoundOutlined, WarningOutlined } from "@ant-design/icons"
+import { Modal } from "antd"
 import { getAssetsByKind } from "@/api/assets"
 import type { AssetItem } from "@/api/assets"
 
 interface Step5VoiceSelectProps {
   selectedVoice: string
   onSelectedVoiceChange: (id: string) => void
+  totalVideoDuration?: number
 }
 
 /** 格式化时长 mm:ss */
@@ -34,10 +36,13 @@ const formatFileSize = (bytes?: number): string => {
 const Step5VoiceSelect: React.FC<Step5VoiceSelectProps> = ({
   selectedVoice,
   onSelectedVoiceChange,
+  totalVideoDuration = 0,
 }) => {
   const navigate = useNavigate()
   const [playingId, setPlayingId] = useState<string | null>(null)
   const audioRef = useRef<HTMLAudioElement | null>(null)
+  const [durationWarningOpen, setDurationWarningOpen] = useState(false)
+  const [pendingVoiceId, setPendingVoiceId] = useState<string | null>(null)
 
   // 获取用户上传的配音素材
   const { data: materials = [], isLoading } = useQuery({
@@ -78,14 +83,38 @@ const Step5VoiceSelect: React.FC<Step5VoiceSelectProps> = ({
     [playingId],
   )
 
-  /** 选中素材 */
+  /** 选中素材（含时长校验） */
   const handleSelect = useCallback(
     (id: string) => {
+      // 如果启用了时长校验，且配音时长不足
+      if (totalVideoDuration > 0) {
+        const material = materials.find((m) => m.id === id)
+        if (material && (material.duration || 0) < totalVideoDuration) {
+          setPendingVoiceId(id)
+          setDurationWarningOpen(true)
+          return
+        }
+      }
       onSelectedVoiceChange(id)
     },
-    [onSelectedVoiceChange],
+    [onSelectedVoiceChange, totalVideoDuration, materials],
   )
 
+  /** 确认使用时长不足的配音 */
+  const handleConfirmUseAnyway = useCallback(() => {
+    if (pendingVoiceId) {
+      onSelectedVoiceChange(pendingVoiceId)
+    }
+    setDurationWarningOpen(false)
+    setPendingVoiceId(null)
+  }, [pendingVoiceId, onSelectedVoiceChange])
+
+  /** 取消选择 */
+  const handleCancelSelection = useCallback(() => {
+    setDurationWarningOpen(false)
+    setPendingVoiceId(null)
+  }, [])
+
   /** 跳转到配音库上传 */
   const handleGoToUpload = useCallback(() => {
     navigate("/app/voices")
@@ -238,15 +267,64 @@ const Step5VoiceSelect: React.FC<Step5VoiceSelectProps> = ({
                   justifyContent: "space-between",
                   fontSize: 12,
                   color: "#999",
+                  alignItems: "center",
                 }}
               >
-                <span>{formatDuration(item.duration)}</span>
+                <span style={{ display: "flex", alignItems: "center", gap: 4 }}>
+                  {formatDuration(item.duration)}
+                  {totalVideoDuration > 0 && (item.duration || 0) < totalVideoDuration && (
+                    <span
+                      style={{
+                        color: "#ff4d4f",
+                        fontSize: 11,
+                        fontWeight: 500,
+                        display: "inline-flex",
+                        alignItems: "center",
+                        gap: 2,
+                      }}
+                    >
+                      <WarningOutlined />
+                      时长不足
+                    </span>
+                  )}
+                </span>
                 <span>{formatFileSize(item.file_size)}</span>
               </div>
             </div>
           )
         })}
       </div>
+
+      {/* 时长不足警告弹窗 */}
+      <Modal
+        title={
+          <span style={{ display: "flex", alignItems: "center", gap: 8 }}>
+            <WarningOutlined style={{ color: "#faad14" }} />
+            配音时长不足
+          </span>
+        }
+        open={durationWarningOpen}
+        onOk={handleConfirmUseAnyway}
+        onCancel={handleCancelSelection}
+        okText="仍要使用"
+        cancelText="重新选择"
+        okButtonProps={{ danger: true }}
+      >
+        {(() => {
+          const pendingMaterial = pendingVoiceId
+            ? materials.find((m) => m.id === pendingVoiceId)
+            : null
+          return (
+            <p>
+              该配音时长（
+              <strong>{pendingMaterial ? formatDuration(pendingMaterial.duration) : "--"}</strong>
+              ）短于视频总时长（
+              <strong>{formatDuration(totalVideoDuration)}</strong>
+              ），播放时配音可能提前结束，建议选择更长的配音素材。
+            </p>
+          )
+        })()}
+      </Modal>
     </div>
   )
 }
diff --git a/apps/web/src/pages/generate/hooks/useSegmentScheduler.ts b/apps/web/src/pages/generate/hooks/useSegmentScheduler.ts
index 3a8e5f05c..74bde795e 100644
--- a/apps/web/src/pages/generate/hooks/useSegmentScheduler.ts
+++ b/apps/web/src/pages/generate/hooks/useSegmentScheduler.ts
@@ -188,9 +188,26 @@ export function useSegmentScheduler(segments: PlaybackSegment[]): SegmentSchedul
           rafRef.current = requestAnimationFrame(tick)
           const nextVideo = videoRefs.current[nextIndex]
           if (nextVideo) {
-            nextVideo
-              .play()
-              .catch((e) => console.warn("[useSegmentScheduler] auto-play next segment failed:", e))
+            const canPlay = () => {
+              nextVideo
+                .play()
+                .catch((e) =>
+                  console.warn("[useSegmentScheduler] auto-play next segment failed:", e),
+                )
+            }
+            if (nextVideo.readyState >= 3) {
+              canPlay()
+            } else {
+              const timeout = setTimeout(canPlay, 300)
+              nextVideo.addEventListener(
+                "canplay",
+                () => {
+                  clearTimeout(timeout)
+                  canPlay()
+                },
+                { once: true },
+              )
+            }
           }
         })
         const accumulatedTime =
@@ -296,12 +313,18 @@ export function useSegmentScheduler(segments: PlaybackSegment[]): SegmentSchedul
     [canPlay, totalDuration, segments, currentSegmentIndex, switchToSegment],
   )
 
-  // 确保 videoRefs 数组长度与 segments 一致
+  // 确保 videoRefs 数组长度与 segments 一致 + 强制预加载
   useEffect(() => {
     videoRefs.current = videoRefs.current.slice(0, segments.length)
     while (videoRefs.current.length < segments.length) {
       videoRefs.current.push(null)
     }
+    // 强制预加载：所有 video 元素挂载后，调用 load() 确保浏览器真正开始加载数据
+    videoRefs.current.forEach((video) => {
+      if (video) {
+        video.load()
+      }
+    })
   }, [segments])
 
   // 组件卸载时清理