Things are getting ugly in the world of connected hi-fis, where pioneer Sonos is facing growing competition – yet is also marshalling its patents in response. The company took aim at one of those rivals, Denon, yesterday with a blog post by its co-founder and general counsel Craig Shelburne. He claimed that Denon’s new range of HEOS products “infringe at least four Sonos patents” with “many of the same elements found in Sonos products, with little or no effort to differentiate features or functionality”. Sonos has filed a lawsuit in Delaware against Denon, although Shelburne holds out the prospect of the companies reaching a settlement. “As a next step, we will offer to sit down with Denon, explain our views and give them time to modify their products. We are not asking for a royalty or other license fee – we just want Denon to build an experience that isn’t copying ours,” he wrote.