Digital DJ software like Rekord Box, Traktor, and Serato use their own algorithms to analyze tracks within the program and are not going to analyze your music perfectly, all the time. Especially if the specific track is busy in arrangement, has live elements, enhanced swing, or maybe simply an older production - which may have been first recorded from tape/vinyl, etc.
Traktor, Serato, and Rekord Box utilize ID tags emended in the master file which allows information such as the title, artist, and album names to be read within the software. Once you import a WAV, AIFF, or MP3 into these programs, it analyzes and creates its own Cue points and Beat Grids (for example) as this information is never originally contained within the master file, like the ones you've purchased with us on Traxsource.
Sometimes you may have to manually edit your tracks within these programs - so the beat is locked to the tempo or “grid” in that specific Digital DJ software - this also helps greatly with playback while in the 'Sync' mode in Traktor or Rekord Box, for example.
Please note: Traxsource is proud to offer many unique, artists and labels. We do not alter masters in any way and tracks sold are an exact digital copy of the masters provided by the content owners.
More info can be found on how to manually set 'Beat-Grids' within these programs below:
How To Set Beat-Grids In Rekordbox
How To Set Beat-Grids In TRAKTOR PRO