Wait, there is more...I installed an expensive, full featured Sony stereo in my boat a few years ago. The following Spring I launched the boat, tied it in my slip, plugged in to shore power, and started on my numerous preparation tasks. I noticed that the stereo was on with the face illuminated but no sound. I made a half hearted attempt to shut the thing off but I was unsuccessful, so I just ignored it. In the weeks that followed I made many more attempts to shut it off but never succeeded. The numerous multi-function buttons had Egyptian hieroglyphs in miniature embossed on them to assist the user in determining some of their functions. I eventually found the manual and I was able to shut it down. Seems it required the user to hold a certain secret button down for a particular time length to accomplish turning it off. I gave that stereo away and began an internet search for a simple stereo. After many hours down the rabbit hole I found a bluetooth Fusion stereo that I can just manage. Has a red button that if you press it long enough it shuts the thing off. Remember the old on/off volume knob? Why did they go and improve on that universally understood, fool proof device?