hi, my volume is all the way up but underneath, there is a circle with a line through it and there is no sound. also there are 4 grey question marks in my tool bar for microsoft messenger, VLC, microsoft project gallery, and microsoft document connection, and my dvd player has an error message that a valid video device could not be found for playback. this all happened within the last couple of days and at the same time. i have had a recent software update. could this be the problem? any suggestions?