The sound in Doom 1.3A (the UB version) DOES work, but you have to plug in external speakers or headphones to hear it. You CAN enable OpeanAL at startup which will force the sound through the internal speakers but this will cause the game to crash after a few minutes. Aspyr have not responded to my questions about why the internal speakers wont work with OpenAL turned off, like it used to before the patch.