I have bought several of these units. In one case, it’s not practical to turn the unit off, so it remains on and works perfectly. On my personal set, I plugged the power cord into the USB of my TV, and when the TV turns off so does the transmitter. Good news is that it comes back on when the TV is turned on, and I don’t have to press the power button…it remembers it was on when the power went off to it. My TV is a Samsung and the USB turns on and off with the TV. Another friend’s Samsung, lesser expensive smaller model, continues to have power to it’s USB socket even when the TV is off. We all use the JBL Clip 2 and Clip 3 speakers and it is great for watching TV. Sound is clear and close to your head, so not turned up loud and doesn’t bother others late at night. I use the optical output from my TV and I notice a slight delay in the sound, but not real noticeable. I don’t know if it’s the unit, or my optical output from the TV. I haven’t tried the other input options. If I watch broadcast channels the optical output doesn’t work and I know the other outputs from the TV would continue to work.