Adjusts the background playback volume.

<percent> Percentage corresponding to which the Background Volume has to be increased or decreased.

• Default volume percentage is 100. In such circumstances, the wavefile will be played without any modification.
• Values below the default volume will decrease the volume and values above the default will increase the background sound. Suppose the command is BgVolume 50; the played back volume will be just half the original sound.
• BgVolume resets to 100% on every call.

:MAIN

   Answer 
   
   BgPlay "bgmusic.wav"
   
   //play welcome message
   play "welcome.wav"
   
   //accept user ID
   BgVolume 50
   play "userid.wav"
   $uid = input(5,4)
   Bgvolume 100
   
   ;......
   ;......
   
   hangup
   goto MAIN