Another pic

Those spots often appear on healthy Oncidium Alliance plants and are not a worry.
Leaf dieback is and the cause is uncertain. Perhaps problems with watering frequency or even lack of Calcium as one of the trace elements in your fertilizer.

Thank you arthurm. That is awesome definitely not what I expected. I expected to hear some sort of fungal infection. You are very knowledgeable. Do you grow orchids for a living...you know about everything...curious where you get all your knowedge?

Simple answer = 42 years of TRYING to grow orchids.

Also, before the Taxonomists changed all the orchids in Genera Odontoglossum to Oncidium, it was easy to tell which ones had Odontoglossum ancestors and would therefore like it a bit cooler and with more shade than say a Cattleya. So it could be that your orchid is just slightly unhappy with your conditions hence the leaf die-back.

The Genera Name of your orchid is now Aliceara.

Hopefully, you will get more suggestions.

I just tossed a Beallara that was slowly dying over the past 2 years. It finally put out a blooming spike but the flowers died on the spike before opening. When I got it, it was gorgeous but something--scale, I think--got all over the pbulbs. I agree with Arthur, the orchids in the oncidium family always seem to have spots. But you can tell the difference between those and fungal spots. The latter are larger and more randomly found. Wish I could give you some growing tips.