Answer: There are several possible causes for the problems you are seeing. One possibility is that you are overwatering the plant and/or overfertilizing it even though it is in active growth, or perhaps have left it sitting in a saucer full of water for too long. This might cause root rot. It is also possible (and this is my hunch) that it has been attacked by the scale insect and that the spots are actually the little flat discs of the scales. These can be gently scraped off by hand or sprayed with insecticidal soap when they are in the crawling stage according to the label instructions.
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