Vista - MSN 98 vs Live XP : audio problem?

I'm trying to communicate
from my msn messenger on 98
to live messenger on xp

I have the webcam on 98;
my friend has not the webcam on xp

I can write text
I can stream webcam images
I can send file
and other things...
my friend receives all

but he can't hear me
(he ses me, but can't hear me)

1) but he can hear other people from Live xp
(never tested with msn 98 other than with me)

3) the little button on the upper-right corner (of the video window)
that toggles audio-speaker on & off
on my friend's Live xp does not change its aspect when pressed
or the related menu item is clicked
(no little circular banning icon overlaps it):
my msn 98 does it

2) but I can regularly use my mic
(= record/speak/hear myself/ talk
with PalTalk communication software to other people)

-------------

So?

Anyone who has Live messenger XP wants to
have 30 second video&audio testing with me?