diff --git a/src/main/export-service.ts b/src/main/export-service.ts
index 4af0bf6..56252a8 100644
--- a/src/main/export-service.ts
+++ b/src/main/export-service.ts
@@ -584,19 +584,6 @@ const detectAssetExtension = (buffer: Buffer): string | null => {
     return 'webp'
   return null
 }
-const htmlArchiveStickerResourceIsValid = async (
-  outputDir: string,
-  value?: string
-): Promise<boolean> => {
-  const filePath = htmlArchiveResourcePath(outputDir, value)
-  if (!filePath) return false
-  try {
-    return detectAssetExtension(await fs.readFile(filePath)) !== null
-  } catch (error) {
-    if ((error as NodeJS.ErrnoException).code === 'ENOENT') return false
-    throw error
-  }
-}
 async function readAvatarAsset(
   source: string
 ): Promise<{ extension: string; buffer: Buffer } | null> {
@@ -941,10 +928,7 @@ async function runSingleExport(
       request.format === 'html'
         ? options.outputFolderName || safeFilePart(request.outputName)
         : `${safeFilePart(request.outputName)}_${exportStamp()}`
-    const root =
-      options.outputRoot ||
-      request.outputDirectory ||
-      (await resolveDefaultExportRoot(outputFolder))
+    const root = options.outputRoot || request.outputDirectory || (await resolveDefaultExportRoot(outputFolder))
     await fs.mkdir(root, { recursive: true })
     const outputDir = join(root, outputFolder)
     const outputPath =
@@ -1236,7 +1220,16 @@ async function runSingleExport(
                 markResourceExists(voiceUrl)
               }
               message.voiceDataUrl = voiceUrl
-              message.voiceDuration = Math.max(1, Math.round(audioBuffer.length / (24000 * 2)))
+              // 读取 WAV 头中的采样率，避免按错误采样率计算时长（Silk 解码为 16kHz）
+              const wavSampleRate =
+                audioBuffer.length >= 44 ? audioBuffer.readUInt32LE(24) : 16000
+              const wavChannels =
+                audioBuffer.length >= 44 ? audioBuffer.readUInt16LE(22) : 1
+              const pcmBytes = Math.max(0, audioBuffer.length - 44)
+              message.voiceDuration = Math.max(
+                1,
+                Math.round(pcmBytes / (wavSampleRate * wavChannels * 2))
+              )
             } catch (error) {
               keepMediaError(
                 request,
@@ -1345,28 +1338,12 @@ async function runSingleExport(
         const reusableImageQuality =
           previous?.exportMediaQuality === 'original' ||
           (request.preferOriginal === false && previous?.exportMediaQuality === 'thumbnail')
-        let reusableMediaExists = false
-        if (reusableMediaType && previous?.exportMediaUrl) {
-          reusableMediaExists = await resourceExists(previous.exportMediaUrl)
-          if (
-            reusableMediaExists &&
-            reusableMediaType === 'sticker' &&
-            !(await htmlArchiveStickerResourceIsValid(outputDir, previous.exportMediaUrl))
-          ) {
-            reusableMediaExists = false
-            resourceExistence.set(previous.exportMediaUrl, Promise.resolve(false))
-            delete previous.exportMediaUrl
-            delete previous.exportMediaType
-            delete previous.exportMediaName
-            delete previous.exportMediaQuality
-          }
-        }
         if (
           reusableMediaType &&
           previous?.exportMediaUrl &&
           (!previous.exportMediaType || previous.exportMediaType === reusableMediaType) &&
           (reusableMediaType !== 'image' || reusableImageQuality) &&
-          reusableMediaExists
+          (await resourceExists(previous.exportMediaUrl))
         ) {
           message.exportMediaUrl = previous.exportMediaUrl
           message.exportMediaType = reusableMediaType
@@ -1478,10 +1455,13 @@ async function runSingleExport(
         } else if (message.contentData.type === 'sticker' && stickerService) {
           const stickerSource = message.contentData.url || message.contentData.thumbUrl
           const result = await stickerService.resolveSticker(stickerSource, message.contentData.md5)
-          const decoded = result.data ? decodeDataUrl(result.data) : null
-          const stickerExtension = decoded ? detectAssetExtension(decoded.buffer) : null
-          if (decoded && stickerExtension) {
-            const name = `sticker_${bufferHashPart(decoded.buffer)}.${stickerExtension}`
+          const decoded = result.data
+            ? decodeDataUrl(result.data)
+            : stickerSource
+              ? await readAvatarAsset(stickerSource)
+              : null
+          if (decoded) {
+            const name = `sticker_${bufferHashPart(decoded.buffer)}.${decoded.extension}`
             const mediaUrl = `media/${name}`
             if (!(await resourceExists(mediaUrl))) {
               await fs.writeFile(join(outputDir, 'media', name), decoded.buffer)
diff --git a/src/main/voice-service.ts b/src/main/voice-service.ts
index 1257be9..36210a3 100644
--- a/src/main/voice-service.ts
+++ b/src/main/voice-service.ts
@@ -125,7 +125,11 @@ export class VoiceService {
           codec: 'silk',
           sourceHash: createHash('sha256').update(silkData).digest('hex')
         })
-        const wavData = this.createWavBuffer(decoded.pcm, 24000)
+        const wavData = this.createWavBuffer(
+          decoded.pcm,
+          decoded.sampleRate,
+          decoded.channels
+        )
         const data = wavData.toString('base64')
         const cacheKey = this.buildCacheKey(
           reference.sessionId,
@@ -239,7 +243,7 @@ export class VoiceService {
 
   private createWavBuffer(
     pcmData: Buffer,
-    sampleRate: number = 24000,
+    sampleRate: number = 16000,
     channels: number = 1
   ): Buffer {
     const pcmLength = pcmData.length