[libvirt-users] Config Errro when Creating a virtual device attachment to backend

Hi, buddy, I want to create a virtual device attachment to backend. The domain is running, and my code phase is as below: xmlConfiguration = "<devices><sound model='es1370'/></devices>"; virDomainAttachDevice(dom,xmlConfiguration); But the exception "libvir: Domain Config error : XML error: unknown device type " happen when running. Is it something wrong in the XML configuration? What should i do to deal with such Config error ? ps: the hypervisor is KVM.