VE F5 not passing tagged vlan traffic across Vxrail ESXI

Hi Guys,

Been working on this and cannot come to a conclusion, our VE F5 which sits in an esxi enclosure, does not work when tagged vlan is configured (this is the way, rest of the other VE F5s are configured across the estate).

However If we untag 1 vlan (and only allows you to untag 1 vlan on the VE) This works for the backend server and traffic passes as we can now see the pool members up, however the front end sits on another vlan and we cannot untag.

The only difference is the other f5s sit on a 'UCS' or HP chassis and the problematic one sits on the 'vxrail'.

my f5 version is 12.1.2 HF2 And the ESXI is version 6.0.

Many thanks if someone can give me a descent answer, i have read most of the forums and nothing helpful.