Mdns not working??

I hava a mycloudex2ultra, everything works fine except the mdns(avahi). It is running but not work, the port 5353 is opening, but can only ping mycloudex2ultra.local for a while after reboot, soon it became bad address. Other PCs and Macs work fine with .local mdns.
Any ideas about it?

Hi @lefthand
Have you opened a Support Case? If not opened, for more information, please contact the WD Technical Support team for the best assistance and troubleshooting: