Reddit mentions of HAVIT Bluetooth 4.1 Transmitter Receiver(aptX), Pair 2 at Once, Mini Wireless Portable Bluetooth Adapter to 3.5mm Audio Devices and Home Stereo, Such as TV, MP3, CD Player, PC, eBook Reader (HV-BT018)

So I haven't tested this, but I THINK this should actually work for what you want. It does require you buying extra stuff though, and it's certainly not the most cost effective thing in the world either.

First off, you need to buy a 2-way headphone splitter. Plug the male end into the audio out on your Dot. Then buy two bluetooth transmitters that plug into audio ports (like this one or this one).

Those transmitters I linked are able to stream to two bluetooth receivers at once, meaning you can stream to all three of your speakers (and potentially upgrade to four later) just using two transmitters.

Then it's just a matter of pairing the transmitters with your speakers. Theoretically, Alexa should start playing through all of them at the same time if you set it up right. Again, not the most cost effective thing in the world, but it should work, assuming you're using the speakers within range of the transmitters anyways. The transmitters need electricity, so there will be wires regardless though. Sadly not much you can do about that as far as I'm aware.

However I have an apple watch and iphone x and it can switch seamlessly between the devices so this is the benefit of the W1 chip. Also if you have the latest range of Ipads I think they all seemlessly connect.

https://www.amazon.co.uk/HAVIT-Bluetooth-Transmitter-Receiver-Wireless-black/dp/B0185GZMMQ/ref=sr_1_11?ie=UTF8&qid=1521115403&sr=8-11&keywords=bluetooth+transmitter

I bought This:
https://smile.amazon.com/gp/product/B0185GZMMQ/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

It's been great and pairs easily.

They didn't tell me anything. I ASSumed. Guess who the ASS is? It's my fiance's. I'm either going to add an aftermarket dongle, or suck it up and get the Mopar kit from Amazon.

Unless, someone knows a better way?

HAVIT Bluetooth 4.1 Transmitter Receiver(aptX), Pair 2 at Once, Mini Wireless Portable Bluetooth Adapter to 3.5mm Audio Devices and Home Stereo, Such as TV, MP3, CD Player, PC, eBook Reader (HV-BT018) https://www.amazon.com/dp/B0185GZMMQ/ref=cm_sw_r_cp_apa_i_mvB9AbGQBM5B5

I got this one from Amazon that works both ways for around the same price. Lets you connect a Bluetooth source to anything with only a 3.5mm plug or lets you use Bluetooth headphones/speakers on anything with only 3.5mm out. Just turn it off, flip a switch, and turn it back on to change modes. Charges with micro-USB and a think a 12ish hour battery life, but i keep mine plugged in all the time. Main reason I got it is to use my Bluetooth headphones on my work computer, but works pretty well hooked up to my TV so as to not wake people up when I use my Xbox (already have a PS4 headset and couldn't justify buying an Xbox one too).

HAVIT Bluetooth 4.1 Transmitter Receiver(aptX), Pair 2 at Once, Mini Wireless Portable Bluetooth Adapter to 3.5mm Audio Devices and Home Stereo, Such as TV, MP3, CD Player, PC, eBook Reader (HV-BT018) https://www.amazon.com/dp/B0185GZMMQ/ref=cm_sw_r_cp_apa_Q-.LBbJQ0KHSP

> I know there are plenty of Bluetooth adapters out there, but this is not what I'm looking for.

But it sounds exactly like what you are looking for. Care to elaborate what a bluetooth adapter like this does not cover? Heck, that thing can even act as a receiver if you want!

I don't see why something like this wouldn't work? https://www.amazon.com/Bluetooth-Transmitter-Receiver-Wireless-HV-BT018/dp/B0185GZMMQ

Though it would add a little clutter to it, maybe you could attach it to the volume thing.