My customer would like to know if there is a way to restrict a Hyper-V user who uses enhanced session mode. Specifically, they want to allow their users to use enhanced session mode for smart cards, but prevent other resources like audio, hard drive and other device redirection for their VMs. Is this possible?
Yes. Hyper-V Enhanced Session Mode uses the Remote Desktop Protocol (RDP) and thus you can use Group Policy to restrict Enhanced Session mode with regard to device and resource and redirection.
Notice here from: Computer Configuration > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Devices and Resource Redirection