🔍 Direct Solution Snippet (Featured Snippet Style)
Zigbee motion sensors
may stop triggering Home Assistant automations because Wi-Fi 6 OFDMA introduces
high-density 2.4 GHz transmissions that raise noise levels and disrupt Zigbee
packets. When OFDMA scheduling intensifies during peak hours, Zigbee frames can
be delayed or dropped entirely. Separating channels, adjusting radio power, and
optimizing Wi-Fi settings usually resolves the issue.
Preliminary
Diagnostic Steps
1. Check Wi-Fi 6
Router Activity Logs
Inspect transmit
power, OFDMA scheduling, and channel bandwidth changes during peak hours. Look
for spikes in grouped uplink/downlink frames.
2. Analyze Zigbee
Network Health
In Home Assistant →
Zigbee → Network Map:
Monitor LQI, RSSI, and packet delivery. Drops during heavy Wi-Fi
activity indicate cross-channel interference.
3. Scan the 2.4 GHz
Spectrum
Use a spectrum
analyzer (e.g., WiFi Analyzer, MetaGeek) to detect:
- Noise floor increases
- Channel congestion
- OFDMA subcarrier bursts
4. Check Motion
Sensor Event Logs
Home Assistant →
Developer Tools → Events → zha_event or zigbee2mqtt logs
Look for delayed triggers or packet loss during problematic hours.
5. Confirm Zigbee
Channel Placement
Zigbee channels
overlapping Wi-Fi 6 channel bonding (20/40 MHz) are more vulnerable to
interference.
Step-by-Step
Technical Fix
1. Change Zigbee
Channel to Avoid OFDMA Overlap
Move the Zigbee
network to channel 15 or 20, which typically avoids Wi-Fi 2.4 GHz
channel 1/6/11 interference.
(Home Assistant → Zigbee → Advanced → Change Channel)
2. Disable OFDMA on
the 2.4 GHz Band
Keep OFDMA only on 5
GHz where needed.
Router Settings → Wireless → Advanced → Disable OFDMA (2.4 GHz only).
3. Reduce Wi-Fi 6
Transmit Power
Lowering 2.4 GHz radio
power reduces noise affecting Zigbee packets.
Set to “Medium” instead of “High”.
4. Switch Zigbee
Coordinator to a USB Extension Cable
Increasing distance
from the router (1–2 meters) reduces RF saturation on the Mesh Network
Health.
5. Reduce Home
Assistant Automation Load
If automations include
conditional checks, reduce event processing delay:
Automations → Edit → Optimize “Wait For Trigger” or remove redundant
conditions.
6. Enable Legacy 20
MHz Channel Mode on 2.4 GHz
Avoid 40 MHz bonding
which harms Zigbee.
Router → Wireless Setup → Bandwidth → 20 MHz only.
7. Update Zigbee
Coordinator & Router Firmware
Install the latest
firmware to improve coexistence algorithms and reduce interference impact.
Preventing Future
Conflict
1. Keep Zigbee and
Wi-Fi on Non-Overlapping Channels
Use fixed channels:
- Wi-Fi: 1 or 6
- Zigbee: 20 or 25
2. Prefer 5 GHz or
6 GHz for High-Traffic Devices
Move cameras, phones,
tablets, and smart displays to 5 GHz or Wi-Fi 6E.
3. Avoid Dense
Sensor Clustering
Spread motion sensors
evenly to prevent packet collisions.
4. Assign Static
IPs to Home Assistant and Routers
Improves Static IP
routing stability and reduces latency for automation triggers.
5. Enable Periodic
Zigbee Mesh Optimization
Restart the Zigbee
network during low-traffic hours to maintain routing stability.