Cats peeing on everything???

I have 3 indoor cats (not in a safe enough area to let them be outdoors). They have 2 huge litter boxes and weve tried have 3 and even 4.

They pee on EVERYTHING. Mainly beds. Our bed, my sons bed, and 2 dog beds in the house, and our couches. Literally anywhere cloth. To a point where our house stinks and im spraying things down and rewashing them every day.

Theyre all fixed and healthy. No signs of UTI's and weve spoken with a vet and they were convinced they didnt have one as well. We have a fountain for them as well so their well hydrated.

Theyve had no lifestyle changes and tbh this has been an issues for a long time but recently started again and a lot more frequently.

Were getting to a point where were overwhelmed by it. Has anyones cats had these issues?? Have you found anything that has worked??