Thanks for reaching out to us, @Masashi_Takezawa!
So we can better understand what you’re experiencing, please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
So we can gain some additional insight, please also see the following:
- Does this behavior occur when playing back to any endpoint? If you play to System Output of the Core machine do you experience this behavior?
- Have you tried power cycling your Core machine, QNAP, endpoints, and networking hardware?
- Do you have any active antivirus or firewall on the Core machine? If so, temporarily disable them. Is there any change in behavior?
Thanks!
Dylan