Chromecast Audio playback also allows higher resolution lossless playback (24/192) than AptxHD. Ultimately AptxHD, as great as it sounds, is still a lossy playback codec. Also by skipping Bluetooth and going with the network WiFi playback of Chromecast Audio you don't have to worry about your phone being in the 30 foot limitation of Bluetooth nor any notification sounds/phone calls from your phone or device interrupting your music
Audioengine's speakers that feature both RCA and 3.5mm inputs keep those inputs alive all the time so you also don't haveh to switch between inputs. If you'd like ou can actually playback through both inputs simultaneously and hear both sources.
On my office A2+ I have a NuPrime uDac handling my desktop PC's audio connected via RCA and the Chromecast Audio dongle is connected via 3.5mm. This makes the A2+ massively more convenient to use as if don't feel like it I don't have to turn on my computer just to listen to music in my home office. I have the option of just streaming to the Chromecast Audio instead. (I run BubbleUPnP Server on local machine that runs basically 24/7 as well as have a Google Play Music subscription which facilitates this.)
]]>