I don't think that this will help. As I wrote - I was all ready back in the shop and checked the other Line6. All behave the same way. I don't believe, that all of them are broken. So this is ether a "marketing feature" to make people believe that line6 amps are louder the others (I guess most of the customers wouldn't turn the volume pot to 5 a clock in a shop if it is loud as hell at 12 a clock...), or this is a bug. If it is a bug then it have to be fixed by line6 with a FW update.
So the question was: Is there is a way to tell them / contact them, other then over the support page.
Honestly speaking I hope it's a bug and not a feature because experience say: marketing will win those battles as long they can increase the numbers with such tricks ...
cu Andreas