I ran into the Amazon skill Alberto Sonorus. I do not fully understand what it does; it seems to create new devices for the (chosen) apps on your phone. Maybe it's helpful for your audio setup?
Thanks for suggesting that however I think this skill is used to open certain apps on your phone. An example of what I am talking about is: I tell alexa to to open the garage door using an actual echo device (echo dot or regular echo) the garage door opens and alexa responds "ok, opening the garage door now" I have that setup in a routine through the alexa app. If i say the same thing to my phone or watch, The garage door still opens however instead of her saying "ok, opening the garage door now" she says "audio actions in routines are not supported on this device" The same thing happens with my ecobee 4 thermostat with Alexa built in however with that it is even a little different because she first responds "audio actions in routines are not supported on this device" but then follows that by "ok, opening the garage door now" Again, i believe this is something Amazon will have to take care of and hopefully will in the near future.