intermittent ora 8103 errors object no longer exists

I have functions that return ref cursors. We are getting these intermittent. The query in question is a join between 2 tables.

1. Table A:Has never changed in production it is 100% static
2. Table B: Gets truncated and reloaded once a day.

I am testing the query out of sqlplus and others are testing it from java so

select package.function(variables)
from dual;

1. Some times it returns data.
2. some times we get ora-8103 to start the query
3. some times we return data and then get ora 8103

I personally have not been able to re-create it. But i can go to someone else's laptop and they run the function with the same variables and get the errors.
I googled this and saw
1. issues with global temp tables. We are not using global temp tables. Just 2 heap tables
2. data gets changed/truncated, etc... during query. No the data is stagnat 3. We do have logging procedures that run before and after the ref cursor parser. They insert to a table from an autonomous transaction. We have never had a problem with this and use this in alot of places.

I am a bit lost on something I can't re-create. None of things on the web or asktom seem to point to my issue since we are basically dealing with static data. None of the data is changing while we are running the queries.

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