Silent Instruments

I tried to change the sound of an instrument, but the program crashed. Now whenever I reopen it, all this instruments are silent. I have tried redownloading the program, and I have downloaded new files, but all of them are always silent. I checked the mixer, and all the instruments show up as nothing. They have a name but no sound, and the program won't let me open the area that lets me select what sound the instruments have.

I have attached a picture of the mixer, and the category that is broken is the thing that says 'sound' and it is blank on every instrument on every program. I cannot open this 'sound' category on any of the programs.