Shoutbox

I have XP with 4 users. Just by 1 user there is no sound when I send a sound to a contact. My soundcard works (I can play songs and I hear sounds from other programs) When I used MSN-plus by another user on the same computer  I hear the sound I send.
Who knows what to do ??

I hope you can understand what I mean. My English is not so very good.

greatings