Odd Behavior....Why?

[sissybritches]

For the last two weeks I've noticed this stange behavior. All my cats( 5
male, neutered, inside only) have started to use the same little box for their
pee. I have five boxs and before this they pretty much used them all. Now
this one box has to be changed completely every 2-3 days & before i only
had to do it once a week. All boxes are scooped daily with complete cleaning
once a week. Has anyone ever heard of cats doing this? and why, if you know.

I wouldn't worry about as longs as they are using the kitty litty litter. Maybe just use 2.And keep those 2 clean. Who knows?
Sissybritches