Many thanks @David-TP I have emailed the log file. In answer to your questions: Can you constantly reproduce this issue? Yes May I know the internet service provider? TPG (www.tpg.com.au) Can you...

Just to add: system was working (including with work laptop connected) without issue for over a year. No recent changes to any configuration etc. that I'm aware of.

System I have a single XE200 unit operating as a router connected to an NBN modem (HFC). (Formerly operated as a two-unit system, but the second is currently disabled). Per ISP requirements:...