Vista - Not receiving sound on msn messenger

I'm on msn messenger and I can talk and the person on the other end can hear me but I can not hear them. video works fine both ways. Everything was working fine just 3 days ago. Can anyone help, I don't have a clue. Sound is turned up on my volume control and turned up on the mixer under the msn messenger. my sound card is an IDT High Definition Audio CODEC. I'm using the built in mic and cam on a Sony Viao VGN-AR670E laptop. I believe that is the correct information. More specs if necessary are listed in my profile. Thanks so much

Perhaps the other persons mic is muted in sound options? You never know.

I have tried it with 2 others today so I don't think that is it but I'm hoping to try it with the same person I did 3 days ago when it was working.....I think she was using a mac but I'm not sure.

ok i understand most of what is happening, can you do the audio and video wizard and see if you can configure sound options within windows live?
if you can hear audio when you play sound in the second attachment then its not your fault, its the opposite person.

Thanks Mr Needs, I did go into the audio video wizard and the sound test worked. I'm now thinking maybe the 2 people it was not working with may have been at fault on their end. What are the odds of that ? At least I have another thing to check into. Thanks very much, I'll post again when I eliminate this possibility.

I just did a call with the person who I was doing web cam with earlier in the week when it worked properly. It was not working with her either and not only that my voice was echoing back at me like it was the first time I tried msn audio video messenger with this computer before I installed service pack 1 (I thought that may have had something to do with it). Then she calls me back again 5 minutes later and it's working fine. We are speaking now as I write this. So I have come to the conclusion this msn messenger is erratic and I may try yahoo to see how that one will work. Or is it something with vista ? Does anyone have a clue ? Thanks again

You can always uninstall and reinstall messenger, maybe somethings gotten messed up with it. Worth a shot.

msn seems to be more consistent than yahoo, as i use both i know, sound is very good on both but webcams leave much to be desired on yahoo.