Hmmm clean installations don't work either? That's very odd. If your using the same iTunes version either upgrade to the latest or find an older version. Another thing to try is install the application using the troubleshoot compatibility and see if that works.
If that doesn't work it might be a hardware or driver issue (which is pretty unlikely).
You could try going into device manager (just type in device manager in your start menu) and just go through everything. If there's a ? mark it's possible you'll need to update that driver.
The only driver i could see causing this problem would be your sound driver. Might also be that your sound card is bad (which is usually built into the motherboard). Before you start investing too much time into that, try doing a clean installation with a different hard drive that's in relatively good working order (and less than 5 years). On top of this, use a different dvd rom (double check, triple check all cable connections to make sure everything is secure) if you can and make sure your copy of Windows 7 disc is clean of dust, dirt and scratches (if it's bad enough to where you need to get a disc scratch kit). Also burned copies or non genuine copies can have this adverse affect as either the burning didn't go right (don't use the same burner) or the the copy you have is not retail (meaning pirated). Can't help you there if it's a pirated copy because for one thing this site does not condone pirating and also there is no way to replicate your issue as well as figuring a solution other than to buy a valid copy of Windows 7.