Some interesting M&A is afoot in the world of hardware and software that's aiming to improve the quality of audio and video communications over digital networks. GN Group -- the Danish company that broke new ground in mobile when it inked deals first with Apple and then Google to stream audio from their phones directly to smart, connected hearing aids -- is expanding from audio to video, and from Europe to Silicon Valley. Today, the company announced that it would acquire Altia Systems, a startup out of Cupertino that makes a "surround" videoconferencing device and software called the PanaCast (we reviewed it once) designed to replicate the panoramic, immersive experience of vision that we have as humans. GN is paying $125 million for the startup. For some context, this price represents a decent return: according to PitchBook, Altia was last valued at around $78 million with investors including Intel Capital and others.