It wasn't bagpipers (unfortunately for us Scottish journalists who like to put a kilt on stories) but a bunch of dancing drummers who had taken to the streets to promote a music festival.
They stopped to give a prolonged exposition of their skills outside the stage door of the Geilguid Theatre. With the result that Dame Helen's performance as the Queen in the play The Audience was all but drowned out by the thud of the drums. Her Majesty exited the stage and came on to the street to command silence. There was an amount of regal effing and blinding involved.