Installed Yosemite, sound disappeared

I have everything on my desktop except the volume control button which was on the top right hand corner of Mavericks has disappeared. Still get the "rush" when I send email and "dings" when I get an incoming but can't seem to find the volume control button. that might be part of your problem??

Are you testing sound by pressing the volume up or down key ? If yes make sure that the checkbox in System pref > Sound >Sound effects > "Play feedback when volume is changed" is being selected ..

Also, check system preferences. Your volumes may be too low. I found the volume control box unchecked in "SP". Checked it and now i have the volume control icon back on the upper right of the screen.

@navy001 > You could recover the Sound icon that was there in top right menu bar by selected the checkbox ""Show volume in Menu Bar " located in System pref > Sound > Sound effects

Here's what worked for me. Open Applications and Utilities. Then open Audio Midi Setup. In my case, both "Mute" boxes were checked for my line out channels. I unchecked them. Problem solved.

I have Yosemite 10.10.3. No problems with sound, until I shut down the IMac and powered back on.

Now I can't get any sound. Sound icon is no longer shown in the upper right menu bar.

I tried going into System Preferences/Sound/Sound Effects.

I can't check any boxes there because everything is grayed out.

I can't check "Play feedback when volume is changed". I can't check

"show volume" in Menu Bar. The alert volume is on, set at 4.

The output volume is on, set at 5. They are grayed out and I can't change them

either, although I have no need to change them since it shows volume is on.

But I don't get any sound at all.