Hello yanpain,
Are you still having that issue? Have you tried the firmware from this page:
Hi
I want to download the latest firmware because I have issues with my printer, but the link is broken :
https://download.support.xerox.com/pub/drivers/3040P/firmware/win7/en_GB/130618_p3040_stdxc.exe
Forbidden
You don't have permission to access /pub/drivers/3040P/firmware/win7/en_GB/130618_p3040_stdxc.exe on this server.
Apache/2.2.15 (Red Hat) Server at origin-download.support.xerox.com Port 443