Hi Henrick. I am not sure on this one but I would suspect it is a bandwidth problem. Hearme do not specify a minimum connection speed but the rest of you spec is fine and I ran happily on a P133 for a while.I don't know why the broadcasting seems to go before the playback but that has been known to happen to others although the only cases that I am aware of involved under powered PCs.
The problem I have with the bandwith idea is that although Jeri has a 56k modem, I am sure that she can only get a 28.8K connection with her ISP and she sounds fine.
I agree that it sounds as if everything is configured correctly and I would suggest that you contact hearme's technical support at http://www.hearme.com/support/support.html?to=hearme-support. I'm sorry I can't be of any real assistance.
Jon