Google Home Mini as mediaplayer + Android CastReceiver not working

I have two Google Home Mini in my installation and they are autodiscovered when HA starts. I have added the Android app CastReceiver into a tablet paired with a bluetooth speaker in order to have another media player.
When the tablet is on, HA outputs the following error at start:
“Setup of platform cast is taking longer than 60 seconds. Startup will proceed without waiting any longer.”
If the tablet is off when HA starts, the two minis are discovered properly.
Has someone a similar setup working? Any hint?