Off-topic as not related to interference, stability or range/coverage but another very important general tip is by the way to be sure to store/copy your Zigbee network backups to another secondary storage location so that you can restore backups in case your Zigbee setup becomes corrupt or primary storage fails completely and you need to reinstall ZHA or Zigbee2MQTT and then want to restore your Zigbee network, (if you are using ZHA then the Zigbee network backups should be part of Home Assistant’s Backup). Zigbee network backups are important since not all Zigbee network data is stored locally on the Zigbee Coordinator adapter (at least not for Zigbee 3.0 networks).
https://www.home-assistant.io/integrations/zha#zigbee-backup-and-restore-in-zha → https://www.home-assistant.io/integrations/backup/
Common tip to achieve off-site backups is to backup Home Assistant’s Backups to Google Drive (cloud):
https://community.home-assistant.io/t/add-on-home-assistant-google-drive-backup/107928