Please follow these quick instructions to get your VB20 to function again:

Tap the Volume up button on the rocker switch (the end with the knub), 10 times. As it gets louder you will hear beeping.  

If you do not hear beeping take off the dome and see if you hear beeping when you tap that button.  

If you do change the dome and your device will work.  

If you do not hear anything when you remove the dome and tap the button, try removing the tube and see if you hear a squealing noise. If you do, change the entire tube.  

If you do not, insert a fresh battery and make sure to leave that fresh battery out 5 minutes after peeling off the sticker before putting it into the device.  

I believe you should have success at this point, if you do not follow the steps in this video for the most unlikely issue.

Click Here for Video