Error when starting SONOS

I am using the Unfolded Circle Remote 3 + Dock 3.

From time to time I get some error when using my SONOS devices:

What can be the reason for this?

At least one situation I now found out:
After a power-reset SONOS does not contain any playlist etc. When then trying to start the SONOS-player, I get this error. In the power on sequence I trigger play towards SONOS. Maybe that is the reason. But shouldn’t this situation be kept properly?

What is step 2 in your power on sequence? If step 1 is power on try and put a delay between step 1 and 2.

Ralf