Even if he weren't infringing on the trademark and everything was above board, Bose would likely still sue him as you can sue anyone for any reason. Would they win?, probably not, but does he have the money to make them lose?, definitely not.
Is that what you'd do if you were Bose? That seems incredibly foolish. It would waste a lot of money, and get them bad publicity, only to stop someone who actually is making their products more attractive.
A smarter idea would be to send a cease and desist. Maybe before that, a nice email to start with. "Hey, we like what you're doing, but unfortunately you'll have to change the name."
