Hi, I have a new Mac Pro and I have some problems during startup. Sometimes, after I switch on the Mac Pro and the startup sound appears I can hear an echo of this sound for about 2 - 4 times. The end of it is repeated. This happens not everytime but roughly every 10th or 20th startup. Another thing which happens not so often is that the Mac Pro hangs completely. I have a black screen and the Mac Pro somehow tries to load something from the DVD drive (which is empty). Every two seconds or so I can hear a sound from the drive - until I switch the Mac off manually. Do you have any ideas what the reason for this is?