My parents have the Roku Simple remote/box, meaning that the Roku remote can't turn the TV on or off or adjust volume. Their Vizio TV remote stopped working and none of the universal remotes I've tried to set up for them have worked so I'm guessing it's something wrong with the TV. Could I buy the Roku remote that has power and volume buttons and program it to work with the Simple box so they could use that to control the TV and Roku? Or do I need to just buy the stick option.
If the TV supports CEC, you may be able to get the voice remote to control it even if the remote sensor in the TV has died. If you enable "1-touch play" under Settings->System->Control other devices and pressing a button on the Roku remote turns on the TV, that would be an indication that the TV supports CEC. Another indication would be if you add the "TV Off" shortcut under Settings->Home screen->Shortcuts and using the shortcut that will be added to your Home Screen to turn off the TV works. However, some TVs that support CEC don't seem to support changing the volume of the TV via CEC, so it may still not work for that.
Check that the TV's remote is really transmitting something by pointing it at your phone's camera and pressing buttons on the remote. You should see flashes of light on the phone's screen if the remote is transmitting. If it is, but the TV doesn't respond when you point the remote at it, there's something wrong with the sensor in the TV.
Yes, you can buy a Roku voice remote which has the TV controls for volume and power and pair it to your current Roku connected to the TV. It will work to control the Vizio TV's power and volume, unless of course there is something wrong with the infrared sensor on the TV preventing it from receiving signals. Since you say the actual Vizio remote as well as universal remotes won't respond when using with the TV.
If the TV supports CEC, you may be able to get the voice remote to control it even if the remote sensor in the TV has died. If you enable "1-touch play" under Settings->System->Control other devices and pressing a button on the Roku remote turns on the TV, that would be an indication that the TV supports CEC. Another indication would be if you add the "TV Off" shortcut under Settings->Home screen->Shortcuts and using the shortcut that will be added to your Home Screen to turn off the TV works. However, some TVs that support CEC don't seem to support changing the volume of the TV via CEC, so it may still not work for that.
Check that the TV's remote is really transmitting something by pointing it at your phone's camera and pressing buttons on the remote. You should see flashes of light on the phone's screen if the remote is transmitting. If it is, but the TV doesn't respond when you point the remote at it, there's something wrong with the sensor in the TV.