Hi @kaykatz,
Welcome to the Roku Community!
Thanks for letting us know about the issue with your Hisense Roku TV, as there is no sound while streaming OTA channels, and the steps you took to resolve it.
Please ensure the antenna cable is properly plugged in and firmly attached to the back of your TV.
If the problem persists, please try restarting your Roku TV by going to Settings > System > Power > System restart (if you do not see a Power submenu, skip to the next step).
Feel free to keep us posted on what you find out, and we'll continue assisting you from there.
All the best,
Chel
Jecheal R.
Roku Community Moderator