Well, that would involve having the CDJ-350s set up as midi controllers with the sound going into channels 3-4 of the SX2 (internal mixer). Be sure to have all switches set correctly.
Since I haven’t set up in Serato for a while, I can’t tell you exactly what settings to use in the software. But it would involve assigning the correct midi controller to the correct tracks and probably setting the correct sound output (this could be as simple as remaining master/cue, but again I am not sure).
Another thing to watch for is having the right Midi device IDs. I know this is something you can set in CDJ-2000s, not sure how on the CDJ-350, but pretty sure it can be done there too.
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