You should also shield both the SSD drive as well as the Rasberry Pi (by using metal enclosures), and be sure to connect Zigbee Coordinator in a USB 2.0 port (not USB 3.0) via a long USB extension cable.
Understand and remember that Zigbee signals are weak and are very sensitive to RMF/EMI/RMI interference so the technology relies on a strong Zigbee network mesh (meaning many Zigbee Router devices) and it makes it much easier to troubleshoot and find real problems if have already optimized your setup and environment to work around that.
Recommend implement workarounds for EMF interference, read these tips which apply to all set ups:
https://github.com/home-assistant/home-assistant.io/pull/18864
(check out whole https://www.usb.org/sites/default/files/327216.pdf too with your perticual set up)
and later also follow best practices:
PS: Also know CC253x hardware is obsolete so recommend that upgrade to CC2652P dongle, see ex: