Freaked me out slightly. He came into bathroom where I was bathing DS4 and asked me why I kept calling him. Told him I hadn't. He responded by clapping his hands over his ears, bursting into tears and telling me "It's horrible, I can hear a voice shouting my name in my ears and it won't stop!"
Calmed him and tried to reassure him that as he had just had a bad cold and has always suffered very severe glue ear after a cold it was probably the gunk in his ears moving about.
Have booked appointment at hearing clinic.
He is usually very calm and straight forward - quite unusual for him to be like this.