I have 2 echo dots set up as a stereo pair in the bedroom. When I shower in the adjoining en-suite, I would like to switch to mono, so that when I connect my portable Bluetooth speaker, (which I take in the shower room with me), I get both channels. At present, I only get the left or right channel and this sounds weird on certain tracks (eg Radar Love). Is there a way to switch to mono via Alexa commands or by using the Alexa app?