At first I thought it wasn't until I did a bit of amateur contortionism and had a good look in the footwells to locate the vents - the drivers vent was shut and the passenger one was pointing too high. Once I opened/adjusted them it did make a difference at lower speeds. At higher speeds even with the tonneau over the passenger side the amount of wind coming into the cockpit overcomes any heat. Chris2002tii is right, the higher speed setting is louder than the engine though...!
Don't feel too bad about the noise. Last week I was a passenger in my friend's hugely expensive all electric Mercedes. Expecting a quiet drive I was amused to find that the only way to keep the windscreen demisted was to have the fan on and the fan made a massive noise, far louder than an engine. Also a message announcing something not available superimposed itself across the sppedometer display blocking sight of the speed. It was one of those computer boxes with a tiny X in the top corner to exit it. The only way to hit this X was to put his hand through the steering wheel! And several seconds not looking at the road. There was also a fake rev counter.... Also, he told me that the auto headlight dipping is so slow that everyone flashes him at night.
