Front panel buttons on Philips rear projection do random things

The buttons on the front panel of my tv do random things when pressed. I have a Philips 55" rear projection and the buttons don't control what their supposed to when pressed. I received the tv for free from a friend because the coolant needed to be changed. I changed the blue and green crt coolant and the picture is like new. I don't know if the buttons on the front of the tv ever worked but they aren't now. The power button seldom works and when it does I have to hold it down for up to 30 seconds and push it several times, the channel buttons turn the tv on and off right away, the input does the same thing and will randomly change the inputs like it should, the volume up button sometimes turns the volume down and sometimes up, the volume down button does the same. When I try to change my settings using the volume buttons on the front (say menu under them), they sometimes move settings in correct direction others not so much. How do I fix these problems?