I have some issues with sound in my game too. I have checked my manufacturer's web-site (Toshiba) and it clearly states I have the most recent sound driver that it recommends for my computer.
Frankly, the main sound issues I see is with the karaoke machine. The music starts but the singer sound doesn't always start with the animations. Or the singing does start and then later the animations for singing are still going on but no singing sound. Personally, I suspect this is a game error with the animations and singing not synced together properly.
Also, I do have the same above issue when a singer tours in my town and performs. There can be sound and no singing or I do hear singing and then suddenly the animations are still going but no singing sound BUT I do hear music sound.
I hear the radios, jut-boxes etc... in game. Only appears to be singing and karaoke machines for me.
Below is my Sound specs.
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Sound Devices
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Description: Speakers (Conexant SmartAudio HD)
Default Sound Playback: Yes
Default Voice Playback: Yes
Hardware ID: HDAUDIO\FUNC_01&VEN_14F1&DEV_5069&SUBSYS_1179FC50&REV_1003
Manufacturer ID: 1
Product ID: 100
Type: WDM
Driver Name: CHDRT64.sys
Driver Version: 8.51.0001.0000 (English)
Driver Attributes: Final Retail
WHQL Logo'd: n/a
Date and Size: 1/27/2011 12:34:12, 1577088 bytes
Other Files:
Driver Provider: Conexant
HW Accel Level: Basic
Cap Flags: 0x0
Min/Max Sample Rate: 0, 0
Static/Strm HW Mix Bufs: 0, 0
Static/Strm HW 3D Bufs: 0, 0
HW Memory: 0
Voice Management: No
EAX(tm) 2.0 Listen/Src: No, No
I3DL2(tm) Listen/Src: No, No
Sensaura(tm) ZoomFX(tm): No
