I just bought one of these at a thrift store and everything works on it for me. Looking for the user manual online and could only find Panasonic SC-PM17 instead of SA -PM17. It seems to be the same model. In searching for it I noticed lots of people asking how to 1. Turn off demo mode (which keeps you from turning the unit off) and 2. Set the clock.
The manual explains: You can't turn off Demo mode until you set the clock. AND, you can only set the clock with the remote. I don't have the remote and I bet a lot of other people don't either.
Hope this helps!