Yes there is an on/off switch. It is on the top as well as the volume control and the aux in selection and they are all pressure sensitive. There are no knobs or switches per se. The aux in and headphone jacks are on the left side (if facing the front of the unit) and the power jack is on the back of the unit down low and on the same side as the other two jacks. Hope this is helpful. Once again going on 2 1/2 years with mine. Great unit!
Hi Jim, Yes it does have a on/off switch as noted. As you face the unit, it will be just off center to the left on the top. you may have to apply light pressure for about one second. On the opposite side you will find the toggle switch for aux in and earphone. You can also turn it off and on with the remote.