I fixed this issue by clearing the "ARP" table in my router. Basically the router can get the mapping of the device MAC addresses to their corresponding LAN IP addresses tangled or outdated when you have many devices that the router keeps an address resolution of to its common IP's.
Typically powercycling or even resetting the router, then the device (Roku) should do this but if you still have the issue after doing this then try setting a static IP in the device connecting to the router to get around this issue. In my case I just used DHCP reservation in my router to associate my Roku's MAC address to another specified local IP other then the IP that was commonly leased by my Roku on my network. This cleared the issue for me at least since this prompted the router to update the ARP table.