如何将mp3文件写入SPIFFS？

如何将来自“https://translate.google.com/tra ... amp;q=hello%20world”的响应作为 mp3 文件写入 SPIFFS 并能够回放。有没有将 mp3 内容保存到 SPIFFS 的示例？
我已经试过了，但没有播放音频
代码：全选 http.begin(tts.c_str());
  // Send HTTP GET request
  int httpResponseCode = http.GET();
  if (httpResponseCode>0) {
     Serial.print("HTTP Response code: ");
     Serial.println(httpResponseCode);
     int len = http.getSize();
     uint8_t buff[len] = {0};
     
     WiFiClient *stream = http.getStreamPtr();
   
     while(http.connected() && (len > 0 || len == -1)) {
        size_t size = stream->available();

        if(size) {
            int c = stream->readBytes(buff, ((size > sizeof(buff)) ? sizeof(buff) : size));
            
         }
        delay(1);
     }
     File file = SPIFFS.open("/helloworld.mp3", "w");
     file.write(buff, len);
     file.close();  
   }
   else {
     Serial.print("Error code: ");
     Serial.println(httpResponseCode);
   }
   http.end();