I believe TD sounds run off of Window's Media Player. Open up window media player and play a sound or song. Look for the (not so obvious) obvious sources of problems, ie. mute accidentally pressed, volume control turned down (double click on your volume control in the task bar, by the time, and there are multiple volume controls that could be turned down) as well as volume control on windows media, check to see if speakers unplugged, and speakers will be disabled if a set of headphones are plugged in. There is also a volume control on TD in the events tab. Sometimes a computer restart will kickstart the sounds to working...