Connecting DDJ Flx4-Sound to Desktop PC

Hello,

Im having trouble connecting my DDJ FLX 4 to my desktop computer to record my sessions via OBS. I connected the device via USB to my PC to use Rekordbox. This works perfect, when I want to output the audio to a speaker directly connected to my DDJ.

Now I wanted to output the audio to my PC and found the option in Rekordbox. Sadly when I turned the option to output to my PC on, I couldn't hear the sound on my headphones. The option to output the audio both to my PC and my DDJ didn't work, since it just disabled audio completely.

After this I decided to connect the DDJ via AUX to my PC and wanted to use this input in OBS. The problem with this was that I kept having a high noise added to the music I was playing which I could'nt turn off. I tried switching cables, but that didn't fix it. After that I even tried to connect another device (a Loop Station) and came to the conclusion that the problem was at the DDJ FLX 4.

Can someone give me advice on what I could try next? Thanks in advance