How do I change a Media Player URL?

[boops boops]

I hope there are some AxWindowsMediaPlayer buffs here. Suppose I put this code in a button Click sub:

With AxWindowsMediaPlayer1
test = Not test
If test Then 
   .URL = "D:\Sounds\Boing.WAV"
Else
   .URL = "D:\Sounds\Plink.WAV"
End If
.CtlControls.Play

The player will obligingly play either Boing or Plink on alternative clicks of the button. But if I try to play two sounds one after the other like this:

.URL = "D:\Sounds\Boing.WAV"
.CtlControls.Play
.URL = "D:\Sounds\Plink.WAV"
.CtlControls.Play

only the second sound will be heard. Putting a lengthy Sleep after the first Play doesn't help; the first sound is still skipped.

Can anyone tell me why this is, or tell me the right way to play two sounds in succession (other than making a playlist)?

cheers, BB