[arch-general] HELP: My webcam stop work.

[Cloud Tao]

My webcam begin can work, but after about 1 minute, the webcam stop work.
when skype, gtalk use webcam all have this problem.

lsmod output:
videobuf2_vmalloc       2469  1 uvcvideo
videobuf2_memops        2283  1 videobuf2_vmalloc
videobuf2_core         24073  1 uvcvideo
videodev              100860  2 uvcvideo,videobuf2_core
media                  10406  2 uvcvideo,videodev

dmesg output:
[ 2379.369663] uvcvideo: Failed to resubmit video URB (-27).
[ 2379.369673] uvcvideo: Failed to resubmit video URB (-27).
[ 2379.369677] uvcvideo: Failed to resubmit video URB (-27).
[ 2379.369681] uvcvideo: Failed to resubmit video URB (-27).
[ 2379.369686] uvcvideo: Failed to resubmit video URB (-27).

when i use mplayer take a photo use driver=v4l2, have a line output:
v4l2: ioctl set format failed: Invalid argument
v4l2: ioctl set format failed: Invalid argument
v4l2: ioctl set format failed: Invalid argument

How to solve this problem? thx very much.