Sample code modification

Signed-off-by: Njiao_yanlin <jiaoyanlin@huawei.com>

zh-cn/application-dev/reference/apis/js-apis-audio.md

@@ -2861,18 +2861,9 @@ async function selectOutputDeviceByFilter(){
 import audio from '@ohos.multimedia.audio';
 
 const audioManager = audio.getAudioManager();
-let audioStreamManager;
+let audioStreamManager = audioManager.getStreamManager();
 let resultFlag = false;
 
-audioManager.getStreamManager((err, data) => {
-  if (err) {
-    console.error(`Get AudioStream Manager : ERROR : ${err}`);
-  } else {
-    audioStreamManager = data;
-    console.info('Get AudioStream Manager : Success');
-  }
-});
-
 audioStreamManager.on('audioRendererChange',  (AudioRendererChangeInfoArray) => {
   for (let i = 0; i < AudioRendererChangeInfoArray.length; i++) {
     console.info(`## RendererChange on is called for ${i} ##`);
@@ -2927,15 +2918,7 @@ audioStreamManager.on('audioRendererChange',  (AudioRendererChangeInfoArray) =>
 import audio from '@ohos.multimedia.audio';
 
 const audioManager = audio.getAudioManager();
-let audioStreamManager;
-audioManager.getStreamManager((err, data) => {
-  if (err) {
-    console.error(`getStreamManager : Error: ${err}`);
-  } else {
-    console.info('getStreamManager : Success : SUCCESS');
-    audioStreamManager = data;
-  }
-});
+let audioStreamManager = audioManager.getStreamManager();
 
 let resultFlag = false;
 audioStreamManager.on('audioCapturerChange', (AudioCapturerChangeInfoArray) =>  {