OK so my cat will be 7 this year.. he has always been great about using the box..over the past few months there have been periods when he uses the litter box and tends to pee on the edge and floor around the box.. when he goes # 2 he always gets it in *THANK GOD* just not sure what the reason for this would be?? Please help!!! I clean the box frequenty.. have tried a shorter box - wondering if as he is getting old he is struggling with height of box? I have always used the same litter?? So very confused!! HELP!