diff --git a/sockets/ws_hook.js b/sockets/ws_hook.js
index 0bc3563..b570153 100644
--- a/sockets/ws_hook.js
+++ b/sockets/ws_hook.js
@@ -37,7 +37,9 @@
   }
   function ToBase64(Bytes) {
     var S = '';
-    var Chunk = 0x8000;   // 分块，避免超长字符串参数
+    // 注意：String.fromCharCode.apply 会把参数数组整包展开成实参，块太大必然爆栈
+    //（V8 实参上限约 6.5 万）。这里每块 8192 字节，远低于上限，且比逐字节拼接快得多。
+    var Chunk = 0x2000;
     for (var I = 0; I < Bytes.length; I += Chunk) {
       S += String.fromCharCode.apply(null, Bytes.subarray(I, I + Chunk));
     }