Realtek Stereo Mix...Can't record

Suddenly I am no longer able to record audio with any programs. I have been using Cyberlink and/or AVS to record VHS and camcorder tapes for years. I have also used Audacity to record audio. Now all of a sudden I cannot.

I am not very tech savvy, but can usually figure things out eventually. This has me stumped. I haven't changed anything. My speakers work fine so it is an input problem. Stereo mix is enabled and is my default for recording. Properties shows that this device is working properly. I also have the latest driver version. I tried troubleshooter and was told the peripheral is not plugged in. I use a Kworld device to capture video. It is definitely plugged in. It captures video fine but not audio on either program. I do not use any peripherals with Audacity. It will not record audio whether streaming from the net or from a program such as Itunes.

Any suggestions would be appreciated. I am at a loss.

@fireberd. I tried it. I saw that windows reinstalled the sound but nothing changed. I should note that all of the capturing programs recognize stereo mix as the audio input, but still no sound. Properties still advises that the device is working properly. One thing that I noticed is that under "levels" in the properties tab the speaker icon was muted. When I unmuted it I got a loud fluttering sound. When I again tried to capture some video, the only sound that recorded was the fluttering, nothing from the tape.

fireberd said:

This could even be a hardware problem with the sound chip.

Do a complete reinstall. First make sure you have the correct hardware sound driver for Win 7 (or Vista). Then Uninstall the sound driver and drivers in the Device Manager. Restart and Windows should install the generic High Definition Audio Device (Driver). Check operation with this driver. You won't have Stereo Mix but mic or line in should work. If that works OK, install the hardware sound driver and check for proper operation.

(I used to live in Laurel).

Unfortunately I have no microphone or analog device (line in) to test the reinstall. My video capture device has a USB connection. Do you recommend that I try the procedure (uninstall sound driver and drivers in device manager) anyway? Also how do I determine what is the correct hardware sound driver for stereo mix?

Thanks again

I tried everything that has been suggested. I am now able to successfully record audio when I capture video. Also I can now see sound levels for Stereo Mix on the "recording" tab. Previously there were no levels visible. I still have a problem with Audacity. When I click the record button the sound becomes terribly distorted. Like a mix of echo, tremelo and vibrato. Perhaps that is another issue.

My primary purpose for this post was to fix the video capture problem and you have helped me with that. Thanks to torchwood and especially firebird for your assistance and patience, I truly appreciate it.