Thanks for reaching out. Have you tried contacting Sharp support yet to inquire further? I'd suggest starting there to see what options or suggestions they can provide.
You can reach them here:
http://www.sharpusa.com/Support.aspxIf you still aren't able to clear up the issue, feel free to send me a private message with your Roku account email address and the serial number of your Roku TV from Settings>System>About. I'll follow up with you directly to see if there is anything else we can recommend.
Thanks!
Tanner
Tanner D.
Roku Community Manager