I have an advent 7016 but i have no sound i have tried to contact advent and explain the problem, but no answ?

Make sure that your speakers are correctly connected to the system and that they have power. After you have done that go into the control panel to access the device manager and make sure that the driver for the sound card is listed with no error marks; such as a red or yellow: X or ! mark, next to it. If it is listed with one of those marks next to it you will need to reinstall that driver.