Yes, the echo dot has the 3.5 mm output and I have one hooked up to my Yamaha 5.1 but I’m too lazy to use it. I’d have to issue another voice command: Alexa, trigger listen echo which turns on the Yamaha and sets the input to the echo dot. I have a problem with the echo dot and the echo in the same room so control was always an issue. Maybe I can get around this by changing the wake word of the dot to computer instead.