S4 delay when pressing "play"

Hi
I bought an S4 mk1 a few years ago and loved using it until I started getting a delay when pressing "Play" (mostly this occurred on the right deck, but also started to happen on the left deck too), which meant I ended up putting the S4 in a cupboard and I went back to vinyl..
I have a show on NYE and would love to try and get the S4 working.
I've been updating my MacBookPro today from OSX 10.6.3, to 10.6.5, to 10.7.4 and now to 10.8.5 and I've tried different installs of Traktor from approximately 2.5 to 2.6.8, the delay when pressing play still happens. When I first boot up and run Traktor everything is fine, the delay starts after about 15-20 minutes.
I have a 2009 2.93 mhz core 2 duo MacBookPro with 4 gb of RAM and an internal 7600 rpm drive.

I've tried turning off quantise and snap which hasn't made a difference.
If i turn off SYNC, then the BPM of the track I'm about to play changes from what it should be (when beat matched or synced) to the normal unchanged BPM of the track.

I've read a few threads here with people having similar problems but I haven't read of anyone actually finding a solution.

So if any kind soul can help an aging DJ out before New Year's Eve, I'd be SO grateful!

Many thanks

 

If Sync is enabled, then Traktor attempts to maintain the phase of the track and results in lag when pressing play depending on what Sync mode is enabled. I have a feeling changing from beat sync to tempo sync may solve your issues.

Otherwise you might need to try disabling sync and manually beatmatching using the tempo faders and just match the number of the new deck to the current deck.

 

Hi
In usually have Tempo sync on and I get the problem regardless of whether im using tempo or beat sync.