The US-only Nightingale sleep system costs $300.
It works with Amazon Alexa devices and IFTTT.
You actually get two units for your money.
Plug in these pass-through outlets on opposite sides of the bedroom.
Then use the Nightingale iOS app to set an ambient noise schedule.
It also comes with a color-changing nightlight; you can turn it off if it bugs you.
The units can play sounds for many different types of rooms.
It can also be customized for people who snore or have tinnitus.