Just purchased a Roku ultra as my main streaming device replacing my PS4. I got it set up and started trails with several replacement streaming services since PS Vue is shutting down. Last night I started the PS Vue app on the Roku and it worked on the 4 main networks (ABC, NBC, etc) but 80% of the other channels will not work. The screen shows the name of the station and the program but it will not connect. I;m able to connect to the station with my PS4, laptop, and phone without issue. Since Im new to roku I do not know that standard trouble shooting steps or what might cause this.
For more information about that channel's features and functionality, you'll want to contact the channel provider support directly to inquire further. Many channels on Roku are developed and maintained by the channel provider themselves.