Issues with NAT type are usually because the routing functions in the hub are not forwarding traffic correctly to the PS4. This can sometimes be resolved by setting up port forwarding to ensure that PS4 specific traffic is forwarded to the correct ports on the PS4. There is a guide on what ports to forward here.
Personally I have my hub in modem mode and use a third party router, so have never had to setup port forwarding, and have no issues with NAT on my PS3 or PS4.
Disclaimer - I don't work for Virgin Media. I'm just another VM user trying to help out so my answers may be wrong If my answer solves your problem please mark it as helpful as it may help others My setup: Vivid 200 Optical fibre with Superhub 2 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.
I agree with SCA1972. My PS4 NAT works ok in modem modem plus own router.
-- Red (VM SH2 AC Beta tester) Running on 200Mb VM service with SH2 AC in Modem Mode, with a ASUS RT-AC5300 router. With this setup I get Fantastic WIRED and WIRELESS Signals in my home. I dont work for VM. But I work in IT, and I know my tech. My advice is at your own risk.
I'm not comfortable with this solution as adding another piece of hardware is surely going to add latency to the connection. Any idea how I can get to nat type 1 (im on nat type 2 atm when my ps4 is in the DMZ). Thanks!