连接到会议的Twilio客户端忽略蜂鸣声参数播放进入/退出音调

Question

鉴于以下Twiml代码段，当我在Chrome 31上运行的javascript客户端拨入会议时，尽管beep="false"和waitUrl=""

，仍会收到进入/退出音调

<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Dial timeLimit="5400" callerId="client:myuser2">
     <Conference startConferenceOnEnter="true" endConferenceOnExit="false" muted="false" maxParticipants="7" beep="false" waitUrl="" > myuser2 </Conference>
</Dial>
</Response>