First things first...

CAN you change patches at all? Does the display show the name of a new patch when you change it? Can you THEN (if it does) go into edit mode, and look and see if it is calling up non-synth waveforms?

Or are you locked into an edit mode?

BTW, don't back up the sample data... you will already have that somewhere (your Ensoniq would lose it every power down).