Turn on FT 6.0 -> Device 'CD-ROM 1' has a backing type that is not supported.

Hi All-

I am attempting at turning on FT in our environment, which I have done quite a few times already.  However in one particular environment when I go to turn it on I get-

Device 'CD-ROM 1' has a backing type that is not supported. {reason.@enum.fault.DeviceNotSupported.Reason

I see the below in the hostd log on the host

CheckIfDeviceCompatibleForFTCommon failed: Device CD-ROM 1 uses unsupported backing type vim.vm.device.VirtualCdrom.RemoteAtapiBackingInfo

This template from which the VM is created has no ISO, this VM has no ISO connected.  It is set to "client device" and also is not ticked.  If I purge the CD/DVD and add it back, I can turn on FT.  Using VDS, dedicated PG and also using VMXNET3 adapter.  I have a workaround but I would like to know what is my root issue.

Any thoughts?