My old damo cool cat chorus sounds muffled all of the sudden

[soulloud]

For the last couple of weeks my old dano cool cat chorus has been sounding really muffled. I had to figure out what it was. I thought it was my amp but I finally narrowed it down to my chorus. I've had this thing for close to 20 years and it has been great. I hate to get rid of it. Does anybody have any ideas about how to fix this?