Oncidium Calico Sweetheart with black Pseudobulbs?

[BKFSRS]

I just noticed that the pseudobulbs on this Onc Calico Sweetheart are turning black. Is this normal? I'm wondering if it's fungus or if they may have gotten too much sun. I've only had this one for about a month and am a beginner. See pictures. Thanks

[WhiteRabbit]

Are those pbulbs firm? Black on one side only, or both?
Could be from high light.

[BKFSRS]

The bulbs are black on both sides and at first I thought they were hard, but they are somewhat squishy. I couldn't resist and I un-potted it and the roots were very compacted in a clump of moss, which the plant came in when I bought it a month ago. I don't have a lot of experience with rotten roots, but it looks to me like at least some of the roots have rotted. How do I know if this is due to a fungus or just over watering? I just potted it in my usual fir bark mix. It is in a bright southern window also, so I guess it could be sun-burndt also. Thanks for responding.

[Wynn Dee13]

They look rotten to me. Especially since you said they are squishy. The roots don't look good either. I think it is do to being over watered. Just my opinion from the pics and your description.

[BKFSRS]

Ok, I guess I'll enjoy the bloom while it lasts and before the whole plant rots!

[Wynn Dee13]

If the plant was sun burnt the leaves would be burnt too not just the pbulbs. And the pbulbs would not be evenly burnt black like they are. So the only thing I can think of is rot. Sorry. You can still try to save it. I don't know if it will live but it might be worth a try.