I've used the S4 for over 10 years and never found how to get round this...
With Sync on:
You press play whilst the other track is playing - it never starts at the right time. Each time you hit play the start point changes, as it appears to be confused by the sync function.
Take sync off and track starts properly from cue point when you hit play, but then you need to manually adjust tempo which is difficult to get the same number as the other deck using the tempo fader. If you later hit sync, it jumps to a different point and ruins the mix.
Only way I can mix with Sync on:
I start my cue point at 16 bars before I would usually hit play & cue. After hitting play in sync mode and I've synced properly with the track playing (adjusting with jog wheel), I move the cue point back 16bars before the point where I wanted to start cueing the track.
So if the cue point is at the start of the track, I would be playing 16 bars of silence before it reaches the point I want to start cueing from.
It just seems like a long way around & I'm unsure if later versions of traktor resolve this issue or if its integral to the design of the software.
When cueing a mix, just like analogue, all I want is for the BPM to be the same speed. If I could find a way to type in the BPM or have BPM matched by number, but not synced, it would be easier.
Any ideas?