Crackling noise on Traktor pro 2

Hey everyone, Ok so i have had traktor pro 2 for around 5 months now and its awesome. Recently im having some problems tho. When I play tracks I get a crackling sound through my speakers, its very annoying. It never happened until recently I changed the 4 port USB hub I have to a new one as the first one broke. I tried linking the DJM 900 up by itself to the software and still I get the crackling during playback so I don't believe that's what it is. I've noticed that the waveform slows a little bit when its playing and the jumping starts as well. I recorded some music and during the playback you can still hear the crackling sound so its defiantly not a speaker problem. I Use a alienware m14x laptop, 2x Cdj 900's, DJM 900 nexus & the X1. Also I have tried adjusting the latency up and down, turning Wi-Fi ect off, using a script to optimize the computer and closed all programs and it still happens. I have updated both Cdj's and the DJM 900 & I checked a Latency checker and said that the system should be able to run it fine as well so I cant figure out what it is. The cpu level in Traktor itself stays very low and doesn't come up quickly or anything causing it to slow. The version I am using is 2.0.3 because when i upgraded to 2.5 it kept crashing over and over (Native Instruments are getting back to me about that). It Happens in all the versions I have tried so its not a 2.0.3 problem either i don't believe. Could it be a recent program i have downloaded or something? Its driving me up the wall I have been trying to figure it out from Monday and have made no progress at all. If anyone could help me it would be very much appreciated, thanks.