VR1600v router connected to NBN via HFC supplies full speed to wifi connected devices without problems throughout. But on rebooting our LAN connected machines, their speed dropped to nearly zero. Still internet, but pings very slow (only 4th set responds), only affecting the LAN connection, while wifi is supplied at full speed. Rebooting the router (while LAN machines are on!) restores full internet speed to LAN network.
It's still a problem (ie. after power failures), as we also log in to our LAN connected machines via VPN when physically absent (can't manually reboot router) and require reliable, speedy internet connection to work.
Solution: Our home network is using static IP addresses (ie. for RDP) and the router (expecting dynamic network IPs) had trouble recognising the static IPs on reboot.
To fix, reconfig router default settings: Network Map - Advanced - Network - LAN Settings - Scroll to 'Address Reservation' and enter the correct static IP address for each connected machine on your LAN network. LAN is now working correctly on reboot.