Apple Studio Display (connected to Mac Book Pro with M1 chip) is muting sound

I have to press "mute" and then "mute" again every time I want to hear something though the apple display speakers... happens as well with YouTube as well as with sound files in the finder as well as in FCPX when playing the timeline... one click elsewhere and its muted again... Annoying.... doesn´t happen when I set the sound output to something else like the rode caster 2 but with just the display it´s every time.. Any ideas?