How to stop a thread that is speaking a given text string

Hello all,

I have a form that is displaying a message box and at the same time started a new thread that speaks the same message. What I want to achieve is to stop the thread speaking the message as soon as I click OK button on the message box. I tried killing the thread using the abort command as soon as I click OK on the message box but the SPEAK process still keeps speaking the whole message even thu the message box goes away.

By the way I am new to VB net and not familiar very much with it. I am just trying to move from VB6 to VB NET. Please help. I assume that the new thread is being killed by the abort command but the speak process might be using some player to speak the message and that player is not being stopped. Any help will be greatly appreciated.

Thanks in advance.