I'm not certain this is root related. You might want to do a root check however. If the roots are rotting you will know to ease up on the watering. I grow some violets and streps in Oyama pots. If the newly potted plant doesn't have a large root system, I let the pots dry out for a day or two between watering. If its large & vigorous, I keep the reservoir filled but even so, a day or so without water usually makes no difference. I do have a fairly large number of plants and there are times when I don't always check my Oyama pots and then they usually do need refilling! Besides the perlite on the bottom, I add extra perlite to my mix.

Terri