I encounter the same problem with my uvc webcam.
The 2 following commands are working fine if I do not run cheese
gst-launch-0.10 v4l2src ! video/x-raw-yuv, width=640, height=480 ! xvimagesink
gst-launch-0.10 v4l2src ! xvimagesink
But, if I run Cheese after the second command, it freezes. If I kill Chesse, the second command is no longer working. To solve the situation, I have to run the first command. After that, Cheese or the second command can be ran without any problem.
I encounter the same problem with my uvc webcam.
The 2 following commands are working fine if I do not run cheese
gst-launch-0.10 v4l2src ! video/x-raw-yuv, width=640, height=480 ! xvimagesink
gst-launch-0.10 v4l2src ! xvimagesink
But, if I run Cheese after the second command, it freezes. If I kill Chesse, the second command is no longer working. To solve the situation, I have to run the first command. After that, Cheese or the second command can be ran without any problem.