I just got the roku soundbar and I love it but the app on my phone won't turn it on or off. All other functions on the app and when I try to turn it off or on the led light blinks but doesn't do anything.
When you open the app on your phone, you click devices in the bottom right, and then select "wake your device" and it turns it on.
Then on your remote home screen, the power button should be on the top right.
I hope this helps!