I have not been able to correlate it to any event in steam. I watched the volume mixer to find out that it was steam. I tried to turn off all notifications but obviously I have missed something. There is no visual cue just this sound in the background.
I appreciate any hints.
Did a download fail/you lose internet while in Big Picture mode?
I don’t think so. I can only open it when I set steam to open in big picture and exit it completely. But I could not find any turned on sound settings there either. I have switched to the beta client maybe that helps? If nothing works I will just mute steam in the volume mixer.