Durabrand PDV-705 portable dvd player plays beautifully but no sound... Any ideas?? went through manual and still no sound on speakers or with headphones

I fixed one with this problem today. The problem was in the switch that is depressed when you close the lid. That switch turns the the screen and the sound off when the lid is closed, and back on when you open it.

I has to remove the back cover, spray the switch with contact cleaner (and immediately press the switch in and out several times quickly to help the contact cleaner to work). This solved it. Put the cover back on and all is well.