If the power button on your RCA universal remote does not turn off any connected devices, either the batteries need to be changed, or you are programming the RCA remote incorrectly. Replace the batteries first, if at all possible; if they appear to be brand-new, try programming in a different code (such as 0000) and attempting to turn off your component. Whether that doesn't work, check to see if the device is programmed, then try a different code to see if your RCA universal remote control may be used anywhere else.