Smart home ecosystems have become more powerful and
interconnected, but they also introduce new challenges—especially when multiple
wireless protocols operate simultaneously. One issue many users notice is that Zigbee
motion sensors suddenly stop detecting movement while a Matter device is
undergoing a firmware update.
This problem can seem confusing, but it has clear technical
causes.
Below is a detailed explanation and how to prevent the
issue.
1. Competing Wireless Traffic and Channel Saturation
Matter devices often use Wi-Fi or Thread, depending on the
model.
When a Matter device performs a firmware update, it
typically downloads a large file over the network, which creates:
* High Wi-Fi traffic
* Dense signal bursts
* Channel congestion
If your Zigbee network uses a nearby channel (e.g., Wi-Fi
channel 1 and Zigbee channel 11), the two signals can interfere.
Result:
Your Zigbee motion sensor struggles to communicate with the
coordinator, causing:
* Missed motion events
* Delayed reporting
* Temporary “freezing” of the sensor
2. Thread and Zigbee Interference (Both Use 2.4GHz)
Many Matter-over-Thread devices use the 2.4GHz band, the
same as Zigbee.
During a firmware update, Thread devices temporarily
increase their communication frequency to ensure data integrity.
This causes:
* RF noise
* Overlapping transmissions
* Short communication blackouts for Zigbee devices
Motion sensors are particularly sensitive because they rely on low-power, low-latency communication.
3. Limited Coordinator or Hub Processing Capacity
Your smart home hub (e.g., SmartThings, Home Assistant,
Hubitat, Echo Hub) handles:
* Zigbee processing
* Thread/Matter processing
* Network safety checks
During a Matter firmware update, the hub may prioritize:
* Update verification
* Packet integrity checks
* Network authentication
This momentarily reduces processing resources for Zigbee.
Impact:
The hub may temporarily ignore or delay Zigbee sensor
packets, making it seem like the motion sensor is offline.
4. Temporary Sleep Mode Interruptions in Low-Power Sensors
Zigbee motion sensors are battery-powered and spend most of
their time asleep.
If the hub is busy with a firmware update, wake-up packets
from the sensor may not be acknowledged.
This leads to:
* Missed wake-up windows
* Delays in motion detection
* Several minutes of silence until the next cycle
5. Weak Zigbee Mesh or Missing Routers
If your Zigbee mesh is not strong enough, interference from
a Matter update can “break” the signal path temporarily.
This happens when:
* The motion sensor relies on a single router
* The Matter device update increases radio noise
* The Zigbee route becomes unstable
A weak mesh makes sensors more vulnerable to external interruptions.
How to Fix the
Problem
1. Change Zigbee Channel to a Cleaner One
In your hub settings:
* Use Zigbee channel 15, 20, or 25
* Avoid channels overlapping with your Wi-Fi router
* Wi-Fi channel 1 →
avoid Zigbee channels 11–14
* Wi-Fi channel 6 →
avoid Zigbee channels 16–20
* Wi-Fi channel 11 →
avoid Zigbee channels 21–26
This drastically reduces cross-protocol interference.
2. Strengthen Your Zigbee Mesh
Add more Zigbee routers such as:
* Smart plugs
* Bulbs
* Dedicated repeaters
This gives the motion sensor alternative communication paths
during interruptions.
3. Move the Hub Away From Wi-Fi Routers
A minimum separation of 2–3 meters is recommended.
4. Schedule firmware updates manually (if possible)
Many hubs allow you to disable automatic Matter updates.
Perform updates during low-activity times.
5. Ensure your Thread network is not overloaded
If you have many Thread devices, add a second border router
to split the load.
Conclusion
Your Zigbee motion sensor stops detecting movement during a
Matter firmware update because the update process causes:
* Radio interference
* Channel congestion
* High hub CPU load
* Temporary communication failures
With proper channel management, mesh strengthening, and
device spacing, you can eliminate these interruptions and keep both Zigbee and
Matter devices working consistently.