On my custom design, I work with a USB cinterion GPRS modem. Everything were going fine but now I`m having problems with the device. On overo fire I get the following error : ehci-omap ehci-omap.O: detected XactErr len 0/8 retry ...  On overo earthstorm I get : 

cdc_acm 1-2:1.12: out of memory (write buffer alloc)
[   27.647644] cdc_acm: probe of 1-2:1.12 failed with error -12

Last week it was working fine.

I guess my design is ok since there is no smoke, but there is one little thing I`m not sure about is the level needed for the usbh_vbus.  I connected 3.3V on this pin (sys_en buffered to 3v) but since the usb standard signal level is 5V should I connect 5V on this pin ?  Since the gumstix is sensitive to input voltage level, I'm scared to try it at 5V.

Thank you