i've got a few problems with iChat and was wondering if anyone could shed some light? i get terrible high pitched feedback when using the macbook's mic and speakers, if i use external speakers it stops... anyone know what can be done about this? instead of iChat, it comes up at the top of the contact list as AIM, but i dont use AOL whats that about? maybe thats the source of my next query... it wouldn't let me share my screen with a mate, it comes up "Failed to start Screen Sharing because: Screen sharing could not be established." - anyone know why this is? i've signed in with my .mac account (60 day trial) but not sure if i'm going to keep the .mac... if you loose .mac do you loose ichat? or at least the ability to talk to other .mac ichat buddies?