We have two stereo HIFI systems and two Pure Chronos idocks in our house, none of which are bluetooth. We have ordered one of these to see if we can get them to link up to bluetooth (i don't really understand the technology myself) with my tablets. Then if that works then maybe the Dot can link to those using bluetooth too
Bluetooth Audio Adapter for Music Streaming Sound System, Esinkin Wireless Audio Receiver Works with Smart Phones and Tablets, Bluetooth Receiver for Speakers
https://www.amazon.co.uk/gp/product/...?ie=UTF8&psc=1