I wanted to ceiling mount an Echo dot in the bathroom and this is what I have come up with.

It's print in place, including all supports (I tried slicer supports but this was way more efficient on material and quicker to print).

Simply make a hole with a standard 127mm or 5inch hole saw, feed your power cable through the side entry on the mount, push the mount into the hole, push the tabs out, then use normal M4 or size 8 screws to pull the tabs tight and grip the plasterboard/drywall. Then it's just a matter of plugging in the cable, pushing the echo dot into the mount and popping the cover over the top.

I'm using an ethernet cable from a PoE network switch with an adapter to convert the 48V down to the 12V required by the Echo Dot, keeping it low DC voltage the whole way. But it would work with the original power supply and the cable routed through the wall or ceiling space.

The speaker cover is made using multiple parts and setting certain parts to have no top and bottom layers, exposing the honeycomb infill that I chose. You can easily change the infill to another pattern or density to get a different look, or print the parts in different colours to get the mesh in a different colour to the frame.