[libvirt] libvirt and virt-manager - Unable to complete install: 'internal error: unsupported input bus usb'

I'm trying create a virtual machine using Xen as hypervisor and virt-manager (libvirt) as the management module. When trying to create the virtual machine I am getting the following error: " Unable to complete install: 'internal error: unsupported input bus usb' " ERROR DETAILS: Unable to complete install: 'internal error: unsupported input bus usb' Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/asyncjob.py", line 75, in cb_wrapper callback(asyncjob, *args, **kwargs) File "/usr/share/virt-manager/virtManager/create.py", line 2276, in _do_async_install guest.start_install(meter=meter) File "/usr/share/virt-manager/virtinst/guest.py", line 461, in start_install doboot, transient) File "/usr/share/virt-manager/virtinst/guest.py", line 397, in _create_guest domain = self.conn.createXML(install_xml or final_xml, 0) File "/usr/lib/python3.7/site-packages/libvirt.py", line 3717, in createXML if ret is None:raise libvirtError('virDomainCreateXML() failed', conn=self) libvirt.libvirtError: internal error: unsupported input bus usb NOTE I: The deploy process follows the instructions here https://www.youtube.com/watch?v=BwkmDM-Gpzc and here https://wiki.centos.org/HowTos/Xen/Xen4QuickStart . NOTE II: Xen Hypervisor uses a CentOS 7 as "domu". MORE INFORMATION ABOUT THE PROBLEM HERE: https://unix.stackexchange.com/q/464186/61742 Thanks! =D