Reply to Suggestions for recording live club sets.....

I've been using Audacity (a daw) to record my live club sets, but i dont like the sound quality or the fact that I have to have another program open and running in the background on my laptop. How it works is i have to revert my headphone jack on my laptop to take audio in signals through the audio settings on my macbook, then run a rca to 1/8 from the record output of the club mixer. Do they sell a device that records through rca's? That i could just plug into the back of the mixer and it saves it onto a sd card or something? Let me know how you guys do it. Thanks