Pictures, where you live, the growing environment and any info you got.

Maybe the roots are growing where they should. The plant knows what it wants. Either it does not like the potting material or it likes its roots exposed. Just guesses. You need to give a lot more information.

I'm in B.C. Canada Lowermainland. Sorry I have no pics. I am a window sill grower. The plant is planted in orchid bark with spag. moss and some perlite. hope this helps. Our humidity is not always optimal for orchids?

I have only had the plant since the fall and transplanted it soon after as the pseudobulbs were becoming shrivelled. I did have some bad roots which I trimmed away then repotted in a mixture of bark, spag. moss and perlite.

Our winters are cool and wet with few freezing days the humidity in the house where they are grown can very from about 30 to 60. Our summers have been hot 25-35c with very low humidity. I suspect the humidity or lack of is the problem

The plant tag reads:Onc. aka Raspberry Chocolate, the plant was purchased from a business that had been just a hobby grower.

I am not sure if this is useful information that can lead to a reolution to my difficulty.

Thank you for taking the time to respond to this issue and sharing your knowledge. Your imput is appreciated

How long have you had that plant? They need to be repotted after 2 or 3 years. Regardless, it the air is too dry they will not like it...

To get fine tuning you have look at the type of Oncidium. Does the tag really say Oncidium Raspberry Chocolate? If you look at the tag and copy exactly what it says, maybe you will get fine tuned help. I thought B.C has a cool humid climate, what sort of temps do you have inside your home?