i reseted my hp envy touch smart and the sound is completely off. By the sound icon on the task bar it has a red bubble with a white cross in it and when i click it says troubleshoot and nothing happens.
Click that speaker icon with that bubble in it. This will bring up the volume slider. There is a speaker icon at the bottom of that slider. Click on it once to 'unmute' the volume. Once you have it unmuted. Clicking anywhere else will hide the volume slider again.