I've had my new MacBook for about a week now and I've noticed a weird thing that I've never seen on any other Mac that I have used. When I wake the machine from sleep or restart it, the volume changes to 50%. Not like its really a big deal to hold the F5 key for a couple of seconds but its slightly annoying since the speakers on the MacBook are not very loud. Is this normal?? I can't seem to find a setting for this anywhere and I'd really like to turn it off.