libv4l2: error dequeuing buf:

Binary package hint: libv4l-0

hello
ubuntu intrepid 8.10 2.6.27-10-generic
xawtv 3.95.dfsg.1-8ubuntu2 0
libv4l-0 0.5.6-1~intrepid1 0

since kernel 2.6.27 i can't use anymore webcam (logitech quick cam express and my tuner tv (hauppauge wintv usb)
both of them are detected but they show only black screen

xawtv wich is working with breezy dapper edgy feisty gutsy hardy does not work with intrepid .
this morning i saw libv4l-0 update from poposed repositori but it does the same as before black screen

lsub
Bus 003 Device 003: ID 0573:4d23 Zoran Co. Personal Media Division (Nogatech) Hauppauge WinTV-USB France 4D23
Bus 003 Device 004: ID 046d:0840 Logitech, Inc. QuickCam Express

modules are loaded

zniavre@zniavre:~/Bureau$ xawtv
This is xawtv-3.95.dfsg.1, running on Linux/i686 (2.6.27-10-generic)
xinerama 0: 1600x1200+0+0
WARNING: No DGA direct video mode for this display.
/dev/video0 [v4l2]: no overlay support
v4l-conf had some trouble, trying to continue anyway
Warning: Cannot convert string "-*-ledfixed-medium-r-*--39-*-*-*-c-*-*-*" to type FontStruct
ioctl: VIDIOC_REQBUFS(count=0;type=VIDEO_CAPTURE;memory=MMAP): Périphérique ou ressource occupé
ioctl: VIDIOC_REQBUFS(count=2;type=VIDEO_CAPTURE;memory=MMAP): Périphérique ou ressource occupé
libv4l2: error dequeuing buf: Argument invalide
ioctl: VIDIOC_DQBUF(index=0;type=VIDEO_CAPTURE;bytesused=0;flags=0x0 [];field=ANY;;timecode.type=0;timecode.flags=0;timecode.frames=0;timecode.seconds=0;timecode.minutes=0;timecode.hours=0;timecode.userbits="";sequence=0;memory=MMAP): Argument invalide
ioctl: VIDIOC_S_FMT(type=VIDEO_CAPTURE;fmt.pix.width=320;fmt.pix.height=240;fmt.pix.pixelformat=0x33524742 [BGR3];fmt.pix.field=ANY;fmt.pix.bytesperline=960;fmt.pix.sizeimage=230400;fmt.pix.colorspace=unknown;fmt.pix.priv=0)Erreur de segmentation
zniavre@zniavre:~/Bureau$

seg fault become when i want to change channel , before it's blank black screen too (oposite to webcam who is never segfault)
with --nodga option it does the same

hope it will be usefull
please ask if you need more infos ..
Thank you very much if somebody read this