Hello James,
Thank you for posting your inquiry on the NVIDIA Networking Community.
Based on the information provided, we recommend to open a NVIDIA Networking Support ticket (Valid support contract required) so our engineers can assist you with this issue, as it can require some extensive debugging. In most of the cases, it is a combination of which platform is being used, f/w and ESXi build.
You can open a support ticket by sending an email to the following email address → networking-support@nvidia.com
Thank you and regards,
~NVIDIA Networking Technical Support