fix record all call does not work on wav format (#211)

* fix #210

* fix throw error without new

* fix throw error without new

lib/record/upload.js

@@ -51,7 +51,7 @@ async function upload(logger, socket) {
 
           /**encoder */
           let encoder;
-          if (obj.record_format === 'wav') {
+          if (account[0].record_format === 'wav') {
             encoder = new wav.Writer({ channels: 2, sampleRate, bitDepth: 16 });
           } else {
             // default is mp3