Ours whistled it was because the ends wernt fitted in the roof bars once the ends were put in no more whistling. It was the wind going through the bars not the roof box that made the noise. You could just cover the ends with tape if you don't have the stoppers.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets