Some lecturers at Waterford Institute of Technology are refusing to correct exam papers from last December.
They say WIT attempted to change an administrative error which saw them paid too much for the work.
The college says this is causing uncertainty about the timing of exam results for students who sat their exams and who would have been due to receive their results early next week.
WIT says it is endeavouring to work through the issues with the union representing the lecturers, the TUI.
The institute has said it is hopeful that the issues will be resolved with minimal impact on students.
The matter has been referred to the Labour Relations Commission.
