Recently replaced the caulk around the the bath tub and a small area under the where the shower head is keeps coming off. I give it 36 hours to dry before anyone uses the shower, and it dries hard. However, after a few showers, it's soft and mushy and starts coming off. The rest of the tub is fine. I have a filter on the shower head that drips while the shower is running (replacing it ASAP), right onto that spot so that's a big part of the problem, but also wondering if the caulk itself is no good. I use DAP, no voc, made for bathrooms. Is that just bad stuff? Or would any caulk no be able to withstand the drip? It only drips a small amount, only when the shower is running. I would think that it would be able to hold up under that.