Pavilion dv6 built-in webcam delays recording video, but not audio

[2shelix]

Product Name and Number: HP Pavilion dv6, FV161AV

Operating System:  Windows 7 64-bit

Error message:  none

Changes made to the system:  none

My actual problem is this: my webcam is suddenly not recording the way it should.  When I hit "record," it will count down from 3 (as per the settings) before saying that it's recording.  Once the count-down is complete and it appears to be recording, the stop button looks as if it is disabled for several seconds (usually at least fifteen seconds, but the longest it's taken so far has been 47 seconds) before it will finally allow me to click the stop button.  After I click it, if I go to view the video, I will see that the camera has recorded the audio from the very beginning, but hasn't recorded any video until the same point at which the stop button was no longer disabled!  In other words, the webcam seems to be working this way:

1)  "Record" button pressed

2)  Count down from 3... 2... 1...

3)  Start recording audio; disable "Stop" button

4)  Record audio for at least 15 seconds; "Stop" button is still disabled

5)  Start recording video; enable "Stop" button

On the times when the webcam seems to magically decide to record the video from the beginning, it also magically decides to delay recording the audio instead.  Usually it's the video that's delayed, though.  

I have already tried updating the drivers through the Device Manager, which says that everything is already up to date.

This is very frustrating.  Please help me resolve this problem.