Not streaming from the net, it's local files. That's just from downloading episodes. Going to compare how much Play Music uses for 2 hours of local playback tomorrow. This all just seems to be more use than from my N5.
I've only been using Spotify so I haven't been able to test, but DSP tunneling seemed to work great on my N5 using locally stored files with Play Music. It's possible doggcatcher isn't taking advantage of that feature or is keeping the internet connection active for whatever reason. It will be interesting to see your results.