Roku remotes can only control tv volume and power, it's up to the tv to control the Soundbar via hdmi-cec. So the Soundbar has to be connected to the tv by HDMI. No HDMI, then yes you will need an universal remote. Look at your local Walmart for the Onn 6 universal remote, about $12.50. It's made UEI, so it accepts advanced codes for individual functions, which 5-digit codes.
Edmund
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