I have one of these and it works, not sure if it's the EXACT modem but it has the 93010 model number
http://www.ebay.com/itm/USB-56k-V90-FAX ... xyOa9R0GqCConexant CX93010-11Z is what I have
Someone should probably add that somewhere to the list of working modems
You can also try rotating which USB port it's in, it sounds silly, but one time no lights would come on at all, I rotated the USB ports a few times and it started working again
Did you try reflashing the SD?