Hi Ann and welcome to the forum.
Your orchid is a member of the Oncidium Alliance. Many of the flowers in this group of orchids contain brown colours which are prefectly nromal so your flowers may be normally coloured. If they are not normally brown they could possibly just be dying off. Orchid flowers eventually die and drop like all other flowers. If you are able, please post some pics of your orchid. This will better enable us to give you good advice.
Go to the American Orchid Society website (
www.aos.org) and download a free culturesheet on Oncidiums. The culture and care of your plant will be the same as as is outlined on the Oncidium culture sheet.
I'm glad you posted because your post reveals a rather serious problem regarding the treatment of orchid names. The name "Cambria" is not a real orchid name at all. It's neither a scientific name nor a common name. It is a name that is used commercially (Mostly in Europe I think) to refer to a whole array of both infrageneric and intergeneric hybrids in the Oncidium Alliance. Vuylstekeara, Beallara, Burrageara, and Oncidium, are just a few of the genera referred to collectively as "Cambria" orchids. What they do is they just drop the proper, correct generic name and replace them all with "Cambria" as if "Cambria" were the genus. It's a pointless and silly practice. the nurseries could just as easily retain the proper name of the plants.
Let us know if you have additional questions!
Happy Growing!