Thanks for the post.
Have you tried rebooting your wireless network to see if that helps the issue you are experiencing? For troubleshooting purposes, have you tried connecting your Roku device to an alternate wireless network to see if the same issue occurs?
In addition, have you already contacted your internet modem provider to see what insight they can provide?
Please keep us posted what you find out and we will be able to assist you further.
Roku Community Moderator