hmm i've just rebooted and this also didn't help...
Maybe its the way my rules/groups are setup...
I have 2 user assignement groups, "USB Allowed" and "USB Blocked"...
USB Blocked has "Everyone" and "Local Users" included, and "AD_USB Allowed (domain.com)" excluded.
USB Allowed has "AD_USB Allowed (domain.com)" included.
I then have a device rule set to Block, Monitor & Notify all Removable Storage devices assigned to the USB Blocked user assignment group.
And a device rule set to Monitor & Notify all removable storage devices assigned to the USB Allowed user assignment group.
Would this be the correct way to have this setup?
Nevermind... Turns out someone had ticked options under the Computer Assignment Group in the Policy Catalog which was overwritting the user settings
I've got USB removable media rules worked as expected now... On to working on optical drive access now.