Amazon Polly TTS breaks Home Assistant Cloud remote access

Last week I succesfully integrated the Amazon Polly TTS service in my HA setup. Since then however, whenever I restart the Home Assistant server, my Nabu Casa remote access is disabled. It says “remote access is being prepared. we will notify you when it’s ready”

I figured out it can be “fixed” by signing out from Home Assistant Cloud, rebooting the host system (from supervisor -> system) and afterwards signing in again. With the next server restart the problem reoccurs.

I checked whether Amazon Polly indeed was the culprit by disabling it (commented out in config) and indeed, restarting Home Assistant Server after that worked as before, including remote access.

My relevant config lines from configuration.yaml:

# Text to speech
tts:
  - platform: amazon_polly
    aws_access_key_id: !secret amazon_aws_access_id
    aws_secret_access_key: !secret amazon_aws_access_secret
    region_name: eu-central-1
    voice: Ruben

Anyone else having this problem, and could it be fixed somehow?