[Help] Momentum 4 : No sound other than voice chat while using discord

Hello everyone,
i have had my sennheiser momentum 4 headphones for about a year now and everytime i use discord voice chat i cant hear anything else than the voice chat. So for example i want to show a youtube video to my friends through discord they will be able to hear the audio while I cant hear a thing. I suppose it has something to do with the settings in the sennheiser app but i was unable to locate any setting that would change this. Any form of help is appreciated :D