I use my quicktime and built-in isight on my macbook to make video chats and e-mail them to my relatives. The audio in my recording have a "cricket like sound" in the backround. This does not appear when i just do an audio recording... only when i do a video recording. I use the built in microphone. I've adjusted the microphone settings in the system preferences still with the same result. How can i get rid of this backround noise during the video recording?