I got a box of Dots yesterday, and set up two immediately to have fun.
Today, I tried to set up one in my bedroom, and it kept stuttering and skipping. Saying "Alexa - what's the weather" gave a response of something like "Right now in <town name> it's <pause, click> degrees with clear <pause> Tonight..."
I thought (a) it was possibly a bad Dot, or (b) WiFi reception in the room was bad (even though I use a WiFi connected clock radio there!).
So I started swapping the devices around, and found they were all doing it.
As you are no doubt aware, there was huge disruption to the internet yesterday by a DDOS attack. I think we may still be seeing fallout from that today.
However, currently all my devices are once more working fine.