There is no sound from any output. Headphones, speakers or bluetooth headset. I don't know if the startup sound uses the soundcard? but as i said I have a startup sound. I have a feeling that the problem came after i upgraded Quicktime to 7.0.2 but I am not sure.
Yes it does. It is a audio tone built in to tell the user that all is well with the initial check. Here is an Apple Support document explaining startup sounds.