I think I would try sliding the plant out of the pot and take a look at the root ball. Two things might be happening, either too much water (is the bottom of the plant sitting in water?) or the potting mix has dried out too much and the water you are putting in is not being absorbed.
If you find a hard, dry root ball when you slide the plant out, you will need to gently loosen up the dry soil by kneading the lump a bit - but try not to break roots! Then put it in a bucket of room temp water and let it soak until it is good and moist again.
If the root ball is soggy, set it on an old, folded cotton towel and let the towel absorb the water from the root ball for a few hours or over night, then don't water until the top of the soil feels dry to the touch - dig your finger in a half inch or so.
Then you also might want to consider re-potting to a larger pot, if the roots are filling up the old pot. Depending where you are in the country, a clay pot might be a better container for that plant than the glazed ceramic one you have, since clay 'breathes' somewhat. But, not if you live in a place with relatively low humidity.