diff --git a/src/decrypt/kgm.ts b/src/decrypt/kgm.ts
index 2fd42a7..9ac5ccf 100644
--- a/src/decrypt/kgm.ts
+++ b/src/decrypt/kgm.ts
@@ -34,12 +34,11 @@ export async function Decrypt(file: File, raw_filename: string, raw_ext: string)
     console.log('kgm: using wasm decoder');
 
     const kgmDecrypted = await DecryptKgmWasm(oriData, raw_ext);
-    // 若 v2 检测失败，降级到 v1 再尝试一次
     if (kgmDecrypted.success) {
       musicDecoded = kgmDecrypted.data;
       console.log('kgm wasm decoder suceeded');
     } else {
-      console.warn('KgmWasm failed with error %s', kgmDecrypted.error || '(no error)');
+      console.warn('KgmWasm failed with error %s', kgmDecrypted.error || '(unknown error)');
     }
   }
 
diff --git a/src/decrypt/qmccache.ts b/src/decrypt/qmccache.ts
index 26ebda7..cfa5ba5 100644
--- a/src/decrypt/qmccache.ts
+++ b/src/decrypt/qmccache.ts
@@ -54,7 +54,7 @@ export async function Decrypt(file: Blob, raw_filename: string, raw_ext: string)
     throw '不支持的QQ音乐缓存格式';
   }
   const tag = await metaParseBlob(audioBlob);
-  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, tag.common.artists == undefined ? tag.common.artist : tag.common.artists.toString());
+  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, String(tag.common.artists || tag.common.artist));
 
   return {
     title,
diff --git a/src/decrypt/raw.ts b/src/decrypt/raw.ts
index 1ef912a..3ff01ba 100644
--- a/src/decrypt/raw.ts
+++ b/src/decrypt/raw.ts
@@ -17,7 +17,7 @@ export async function Decrypt(
     if (ext !== raw_ext) file = new Blob([buffer], { type: AudioMimeType[ext] });
   }
   const tag = await metaParseBlob(file);
-  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, tag.common.artists == undefined ? tag.common.artist : tag.common.artists.toString());
+  const { title, artist } = GetMetaFromFile(raw_filename, tag.common.title, String(tag.common.artists || tag.common.artist));
 
   return {
     title,
diff --git a/src/decrypt/utils.ts b/src/decrypt/utils.ts
index d58a276..94b7593 100644
--- a/src/decrypt/utils.ts
+++ b/src/decrypt/utils.ts
@@ -93,6 +93,7 @@ export function GetMetaFromFile(
 
   const items = filename.split(separator);
   if (items.length > 1) {
+    //由文件名和原metadata共同决定歌手tag(有时从文件名看有多个歌手，而metadata只有一个)
     if (!meta.artist || meta.artist.split(split_regex).length < items[0].trim().split(split_regex).length) meta.artist = items[0].trim();
     if (!meta.title) meta.title = items[1].trim();
   } else if (items.length === 1) {
@@ -136,7 +137,9 @@ export function WriteMetaToMp3(audioData: Buffer, info: IMusicMeta, original: IA
     if (frame.id !== 'TPE1' && frame.id !== 'TIT2' && frame.id !== 'TALB') {
       try {
         writer.setFrame(frame.id, frame.value);
-      } catch (e) {}
+      } catch (e) {
+        console.warn(`failed to write ID3 tag '${frame.id}'`);
+      }
     }
   });
 
@@ -176,7 +179,7 @@ export function WriteMetaToFlac(audioData: Buffer, info: IMusicMeta, original: I
 export function RewriteMetaToMp3(audioData: Buffer, info: IMusicMeta, original: IAudioMetadata) {
   const writer = new ID3Writer(audioData);
 
-  // reserve original data
+  // preserve original data
   const frames = original.native['ID3v2.4'] || original.native['ID3v2.3'] || original.native['ID3v2.2'] || [];
   frames.forEach((frame) => {
     if (frame.id !== 'TPE1'
@@ -188,7 +191,7 @@ export function RewriteMetaToMp3(audioData: Buffer, info: IMusicMeta, original:
       try {
         writer.setFrame(frame.id, frame.value);
       } catch (e) {
-        throw new Error('write unknown mp3 frame failed');
+        throw new Error(`failed to write ID3 tag '${frame.id}'`);
       }
     }
   });
diff --git a/src/decrypt/xm.ts b/src/decrypt/xm.ts
index 4f64894..1c487cf 100644
--- a/src/decrypt/xm.ts
+++ b/src/decrypt/xm.ts
@@ -49,7 +49,7 @@ export async function Decrypt(file: File, raw_filename: string, raw_ext: string)
   const { title, artist } = GetMetaFromFile(
     raw_filename,
     musicMeta.common.title,
-    musicMeta.common.artists == undefined ? musicMeta.common.artist : musicMeta.common.artists.toString(),
+    String(musicMeta.common.artists || musicMeta.common.artist),
     raw_filename.indexOf('_') === -1 ? '-' : '_',
   );
 
diff --git a/src/utils/qm_meta.ts b/src/utils/qm_meta.ts
index 5824e8f..ea31795 100644
--- a/src/utils/qm_meta.ts
+++ b/src/utils/qm_meta.ts
@@ -40,7 +40,7 @@ export async function extractQQMusicMeta(
     if (musicMeta.native[metaIdx].some((item) => item.id === 'TCON' && item.value === '(12)')) {
       console.warn('try using gbk encoding to decode meta');
       musicMeta.common.artist = '';
-      if (musicMeta.common.artists == undefined) {
+      if (musicMeta.common.artists) {
         musicMeta.common.artist = iconv.decode(new Buffer(musicMeta.common.artist ?? ''), 'gbk');
       }
       else {
@@ -70,7 +70,7 @@ export async function extractQQMusicMeta(
 
   return {
     title: info.title,
-    artist: info.artist || '',
+    artist: info.artist,
     album: musicMeta.common.album || '',
     imgUrl: imageURL,
     blob: await writeMetaToAudioFile({