[Solved] How to fix Matter Accessory Showing ‘No Response’ in Apple Home App caused by IPv6 mDNS Multicast DNS routing failure between 2.4GHz Wi-Fi and Thread Border Router on Apple TV 4K

[Jerry Gomez]

Diagnostic Hardware Specs: Apple TV 4K (3rd Gen) 128GB Wi-Fi + Ethernet | OS Version: HomePod OS 18.1 | Archive Source: Apple Support Community #256242564

I am running into a persistent issue on my Apple TV 4K (3rd Gen) 128GB Wi-Fi + Ethernet running HomePod OS 18.1.
Whenever the machine encounters IPv6 mDNS Multicast DNS routing failure between 2.4GHz Wi-Fi and Thread Border Router, the following diagnostic log appears in Console:

homed: [Matter] Transport connection dropped for NodeID 0x56b9: IPv6 unreachable via Thread mesh

I verified that hardware connections are intact and tested across different power sources. What is the verified diagnostic procedure to permanently eliminate this symptom?

Mac Studio M2 Max (64GB) | Neumann KM184 Pair | Logic Pro 11 | Barcelona, ES

Classical Pianist & Spatial Audio Arranger | "Verified Apple Discussions Archive"

[Hannah Brooks]

Apple Recommended / Verified Community Solution

This canonical solution was verified and marked as solved in the Apple Support Community archive.

Enabling IGMP snooping / multicast forwarding and rebooting primary Thread Border Router.

Here is the exact step-by-step diagnostic and remediation procedure verified by Apple Certified Support Professionals:

1. In home router Wi-Fi settings, enable IGMP Snooping and disable ‘AP Isolation’.
2. Power cycle your primary Thread Border Router (Apple TV 4K connected via Gigabit Ethernet).
3. Power-cycle the unresponsive Matter accessory for 10 seconds to prompt a fresh Thread mesh re-route.

Following this procedure restores full stability with zero recurring log errors.

MacBook Air 15″ M2 (16GB) | GoPro Hero 12 Black | Apple Watch Ultra 2 | Stockholm, SE

Apple Certified Support Professional (ACSP) | Digital Nomad & Travel Filmmaker

[Author]

Posts