diff --git a/src/utils/metadata.d.ts b/src/utils/metadata.d.ts
index 2702ff4..1e146da 100644
--- a/src/utils/metadata.d.ts
+++ b/src/utils/metadata.d.ts
@@ -6,6 +6,7 @@ export interface FileMetadataResult {
   detectedMarkers: string[];
   provenanceRisk: 'High' | 'Low';
   raw: unknown;
+  parseError?: string | null;
 }
 
 export function readFileMetadata(file: File): Promise<FileMetadataResult>;
diff --git a/src/utils/metadata.js b/src/utils/metadata.js
index a921079..36cb772 100644
--- a/src/utils/metadata.js
+++ b/src/utils/metadata.js
@@ -1,9 +1,37 @@
-import { parseBlob } from 'music-metadata-browser';
 import ID3Writer from 'browser-id3-writer';
 
 const AI_MARKERS = ['ai','generated','suno','udio','boomy','aiva','soundraw','mubert','stable audio','provenance','c2pa','content credentials','watermark','synthetic','elevenlabs'];
+const MARKER_REGEX_CACHE = new Map();
 
-function collectStrings(metadata) {
+let parseBlobLoader = null;
+
+async function getParseBlob() {
+  if (parseBlobLoader) return parseBlobLoader;
+  parseBlobLoader = import('music-metadata-browser').then((mod) => {
+    const fn = mod?.parseBlob || mod?.default?.parseBlob;
+    if (typeof fn !== 'function') {
+      throw new Error('music-metadata-browser parseBlob export not found');
+    }
+    return fn;
+  });
+  return parseBlobLoader;
+}
+
+function escapeRegex(value) {
+  return value.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+}
+
+function markerToRegex(marker) {
+  if (MARKER_REGEX_CACHE.has(marker)) return MARKER_REGEX_CACHE.get(marker);
+  const escaped = escapeRegex(marker);
+  const regex = marker.length <= 2
+    ? new RegExp(`\\b${escaped}\\b`, 'i')
+    : new RegExp(`(?:^|\\W)${escaped}(?:$|\\W)`, 'i');
+  MARKER_REGEX_CACHE.set(marker, regex);
+  return regex;
+}
+
+function collectStrings(metadata, fileName = '') {
   const common = metadata?.common || {};
   const native = metadata?.native || {};
   const values = [common.title,common.artist,common.album,...(common.genre || []),...(common.comment || []),common.encodedby,common.publisher]
@@ -16,21 +44,32 @@ function collectStrings(metadata) {
       if (frame?.value && typeof frame.value === 'object') values.push(JSON.stringify(frame.value));
     });
   });
+  if (fileName) values.push(String(fileName));
   return values.join(' | ').toLowerCase();
 }
 
 export async function readFileMetadata(file) {
-  const parsed = await parseBlob(file);
-  const searchable = collectStrings(parsed);
-  const detectedMarkers = AI_MARKERS.filter(marker => searchable.includes(marker));
+  let parsed = null;
+  let parseError = null;
+
+  try {
+    const parseBlob = await getParseBlob();
+    parsed = await parseBlob(file);
+  } catch (error) {
+    parseError = error;
+  }
+
+  const searchable = collectStrings(parsed, file?.name || '');
+  const detectedMarkers = AI_MARKERS.filter((marker) => markerToRegex(marker).test(searchable));
   return {
-    format: parsed.format?.container || file.type || 'unknown',
-    title: parsed.common?.title || file.name.replace(/\.[^.]+$/, ''),
-    artist: parsed.common?.artist || '',
-    genre: parsed.common?.genre?.[0] || '',
+    format: parsed?.format?.container || file.type || 'unknown',
+    title: parsed?.common?.title || file.name.replace(/\.[^.]+$/, ''),
+    artist: parsed?.common?.artist || '',
+    genre: parsed?.common?.genre?.[0] || '',
     detectedMarkers,
     provenanceRisk: detectedMarkers.length > 0 ? 'High' : 'Low',
     raw: parsed,
+    parseError: parseError ? String(parseError?.message || parseError) : null,
   };
 }
 
@@ -38,10 +77,20 @@ export async function writeMP3Metadata(file, metadata) {
   const buffer = await file.arrayBuffer();
   const writer = new ID3Writer(buffer);
   writer.removeTag();
-  if (metadata.title) writer.setFrame('TIT2', metadata.title);
-  if (metadata.artist) writer.setFrame('TPE1', [metadata.artist]);
-  if (metadata.genre) writer.setFrame('TCON', [metadata.genre]);
-  writer.setFrame('TENC', 'SpectraCleanseAI Browser Quick Cleanse');
+
+  const safeText = (value) => {
+    if (typeof value !== 'string') return '';
+    return value.replace(/\u0000/g, '').trim().slice(0, 500);
+  };
+
+  const title = safeText(metadata?.title);
+  const artist = safeText(metadata?.artist);
+  const genre = safeText(metadata?.genre);
+
+  if (title) writer.setFrame('TIT2', title);
+  if (artist) writer.setFrame('TPE1', [artist]);
+  if (genre) writer.setFrame('TCON', [genre]);
+  if (title || artist || genre) writer.setFrame('TENC', 'SpectraCleanseAI Browser Quick Cleanse');
   writer.addTag();
   return new Blob([writer.getBlob()], { type: 'audio/mpeg' });
 }