Reply to Routing monitor channel to a channel to record?

Hi very new to the community and I've read a lot of posts but none seem to help me specifically with my problem which leads me to believe it may be a hardware issue or possibly me just being a dumbass (most likely).

Any help would be much appreciated.

Basically I can record whatever is being played on my computers sound output on the S4 routing the sound audio from my computer into a spare channel on the S4 and use the volume controls as a gain. However I would like to record directly on the internal mixer without going through any other soundcards or RCA cables as I am doing now. I can get the monitor audio signal to play through the S4 but not on any of the recording channels so I'm just using the main volume control as a master without being able to control the gain or get an audio signal into the mix recorder, thus I have to re-route it into a channel to record. I have tried basically every possible input/output setting on both the Traktor prefs and in my computers onboard prefs for playback and recording but can't seem to find a combination to channel the computers monitor audio into a channel to record on the mix recorder. I know I'm repeating myself here but just want my problem to be clear. Should I be duplicating the master channel in any of the other outputs/inputs in order to re-route the signal so its not just passing through the S4 but goes into a channel so I can record?

Thanks in advance for any help, apart from that the S4 is amazing, as you all know!