USB webcam microphone produces clicking noise

[bugsrep]

I am using a Dell Latitude D810 laptop with a USB QuickCam? Deluxe for Notebooks webcam & microphone.

This problem appeared in Skype for Linux. When I talked to other people they and I could hear clicking noise every 4-6 seconds. There were other people on Skype forums who experienced similar problems. Nothing helped me.

While trying to resolve this issue, I ran PulseAudio Volume Control and opened the Input Devices tab. There is microphone signal strength meter (a blue line that jumps back and forth). Most of the time the blue line is at the left edge unless I speak loudly. However, from time to time (within a few seconds) this line jumps to 100% even though I make no sounds. Then the line gradually goes back to the left within less than a second. This behaviour is independent from the sensitivity settings. I attach a file with the sensitivity set to 10% but the signal level still jumps to 100%.

Skype is not loaded, so it is not related to it. There is nothing wrong with the hardware because the microphone works fine in Windows XP (using the native Windows driver).

[bugsrep]

The microphone is not physically overloaded but the signal strength meter shows that it is.

[lennart]

Please verify that this is a problem specific to PA. Please try Skype and make it bypass PA by going to the raw ALSA device. If the problem exists there, too, please file a bug against ALSA.