question on audio and video playing on android

Well it's guessing time again because you don't give a lot of information.
 
So my guess is the url your using correct.
 
Have you tried using the URL in a bowser ?
Have you tried using google to look up the error ?
 
Perhaps if you supplied the OS version/API version and code segments that you think might be causing the issue alone with stack trace others may be able to help you out.
 
/Darren