How to restore Win 7 Pro System sounds? corrupted!?

I looked at this tutorial first:
Windows Media Player - Rebuild Corrupted Libraries[2]=Media

But my problem remains.

The sounds themselves are wrong/bad/corrupt. Sounds do play on this computer, as in videos, movies, etc. and I can play the sounds in the Office sound library OK at C:\Program Files (x86)\Microsoft Office\Office14 (applause.wav, etc.)

However, all the SYSTEM sound schemes (Afternoon ... Windows Default) sound like a burst of static (or more closely like a recording of a room were the mic was on and nothing recorded.)

The NO SOUNDS sound scheme, is appropriately silent, but the rest is garbage. (Asterisk, Critical Stop, Default Beep, Windows Logoff, etc. all fail.)

How can I restore these? (No, not re-installing Windows.)

You can try SFC /SCANNOW Command to see if System files can be repaired.

Is this factory preinstalled Win7 which is the worst possible install one can have of Win7, larded with bloatware and useless duplicate utilities which interfere with better versions built into Win7?

That's why most tech enthusiasts will not run such an install but instead Clean Reinstall - Factory OEM Windows 7. Everything is provided in the blue link tutorial.

At the minimum I'd Clean Up Factory Bloatware.

If this doesn't resolve performance problems, work through these Troubleshooting Steps for Windows 7.