To keep the source IP unchanged

Hi,You can try creating a more specific NAT to achieve this for outbound traffic.nat(dmz) 2 y.y.y.12 255.255.255.255global (ouside) 2 x.x.x.170 netmask 255.255.255.255Thanks,

No don't remove existing NAT. Add this one as well.

Hi Sami,It looks like the issue of Source NAT vs Destination NAT. You have not mentioned the version of your software.Adding the following line should fix this for you.static (outside,dmz) y.y.y.12 x.x.x.170 netmask 255.255.255.255Cheers,Mubarak