Playback area NOT greyed out but cursor does not move and no sound. (also no sound when note input)

I had a similar problem with my mac, so now I'm trying to use the program on my Windows computer.
I have an audio interface (TC Electronic - Desktop Konnekt 6) and studio monitors that are connected to it. my audio interface uses a firework connection.

So... I have no sound when note input and playback does not work. It seems to start but no cursor move or sound, anything. It stays like that till I stop.

I tried every possible PortAudio options. But if I use a headphone (not using my audio interface), it works. Probably it will also work if I use external speakers that are directly connected to PC. I also tried re-installing and factory reset. Funny thing is that it was working before. Now it just stopped. Couple of days ago it again worked but for a moment.

I googled to see if anyone find a similar problem like this but I failed to find. Has anyone ever had this problem before? It seems like MuseScore does not want to deal with my audio interface at all...

I have a soundfont and I tried other soundfonts as well.

Thank you for your help in advance.