Cause: audio device ES1370 is available in RHEL-6, but not in RHEL-7.
Consequence: guests configured with this device cannot be migrated from a RHEL-6 host to a RHEL-7 host.
Workaround: reconfigure the guest to use AC97 instead of ES1370. To do this in libvirt domain XML, replace es1370 in
by ac97, and reboot the guest.