No sound on YouTube or flash objects

[MK41144]

My laptop is a Dell Inspiron 1520 with Windows 7 professional. Out of the blue one day the sound stopped working on YouTube. I then noticed that it was also not working on my Windows sidebar gadgets. Windows alert sounds work and I can play music in MediaMonkey. However, Windows Media Player will not open. It crashes as soon as it comes up. Yesterday I tried to open Rosetta Stone and it says "No output device found."

I can not figure out what is wrong. First thing I did was update my sound card driver. I also re-installed Adobe Flash. I tried all the fixes on this site: Codec Guide: 10 fixes for sound problems in Flash videos

If someone could help me figure this out I'd really appreciate it. Thanks.

 

[office politics]

any errors in event viewer?

Open Event Viewer

 

[MK41144]

Nothing related to sound that I can see. Here's the entry for Media Player crashing:

Log Name: Application
Source: Application Error
Date: 6/10/2011 2:46:31 PM
Event ID: 1000
Task Category: (100)
Level: Error
Keywords: Classic
User: N/A
Computer: Mike-PC
Description:
Faulting application name: wmplayer.exe, version: 12.0.7600.16667, time stamp: 0x4c7dc5a1
Faulting module name: KERNELBASE.dll, version: 6.1.7600.16385, time stamp: 0x4a5bdbdf
Exception code: 0xc06d007e
Fault offset: 0x0000b727
Faulting process id: 0x1990
Faulting application start time: 0x01cc279eb3955fd5
Faulting application path: C:\Program Files (x86)\Windows Media Player\wmplayer.exe
Faulting module path: C:\Windows\syswow64\KERNELBASE.dll
Report Id: f4cba391-9391-11e0-ae10-001d09b2598f
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Application Error" />
<EventID Qualifiers="0">1000</EventID>
<Level>2</Level>
<Task>100</Task>
<Keywords>0x80000000000000</Keywords>
<TimeCreated SystemTime="2011-06-10T18:46:31.000000000Z" />
<EventRecordID>44040</EventRecordID>
<Channel>Application</Channel>
<Computer>Mike-PC</Computer>
<Security />
</System>
<EventData>
<Data>wmplayer.exe</Data>
<Data>12.0.7600.16667</Data>
<Data>4c7dc5a1</Data>
<Data>KERNELBASE.dll</Data>
<Data>6.1.7600.16385</Data>
<Data>4a5bdbdf</Data>
<Data>c06d007e</Data>
<Data>0000b727</Data>
<Data>1990</Data>
<Data>01cc279eb3955fd5</Data>
<Data>C:\Program Files (x86)\Windows Media Player\wmplayer.exe</Data>
<Data>C:\Windows\syswow64\KERNELBASE.dll</Data>
<Data>f4cba391-9391-11e0-ae10-001d09b2598f</Data>
</EventData>
</Event>