Many thanks for your query. It’s a difficult one to provide a short answer to, but I would certainly recommend that you consider a Speech and Language Assessment to a) ascertain the nature of this difficulty you describe and b) highlight possible coping strategies to use, particularly in interview situations/contexts.
A list of private speech and language therapists is available at: http://www.iasltpp.com/directories.html
You may also be able to access an SLT assessment through your local health office, HSE, although it’s likely that you will encounter a waiting list for this.
In my experience, as a former speech and language therapist, identifying and naming the difficulty/challenge can go some way towards addressing it, and then identifying suitable techniques to minimize the difficulty is usually the natural next step.