Whats wrong with my Line 6 Spider Jam?

I have a line 6 spider jam. The different amp models sound way different, the tremolo and the delay seems to come on by itself, And the volume is lower than normal. What can it be. I thought it was the board with the controllers (knobs) on it, so I replaced it. It didn't fix the problem. I had to replace the lcd screen, due to not being able to read it. I quit sitting on the amp. But I don't think that had anything to do with the issues Im having with the sound. And Im also having issues with the paly/record buttons. I have to use the foot pedal to turn it off and on.