interfacing a web cam by pwc driver on a BB rev c2

Hi,

I have Philips PCVC740K webcam connected to BB by hub and all works only with a resolution of 160X140. If I try to set a bigger resolution I have this error:

root@beagleboard:~# setpwc -S 640,480,10
setpwc v1.2, © 2003-2006 by folkert@vanheusden.com
[ 368.406860] pwc: isoc_init() submit_urb 0 failed with error -28
[ 368.412902] pwc: isoc_init() submit_urb 1 failed with error -28

If I use a resolution bigger than 160X140, I have the same error capturing images by all the programs …
I have installed: http://www.angstrom-distribution.org/repo/?pkgname=kernel-module-pwc
and my kernel is 2.6.32.

What could be the problem?

Thanks
Luciana