I have a cat who is about four years old. Within the last year, she has developed a fear of thunder. She can hear it before I can, starts mewing very loudly and rapidly. She runs for cover in the basement, continues to vocalize and be very scared. She can also hear it after I can. Sometimes it scares the poop out of her. Any suggestions? My vet has suggested a CD of thunder in the background to desensitize her. So far that hasn't worked, but I haven't played it for extended periods. Any other suggestions?