ZOG + Col preferred DJ software Mixxx has had a new release of stable version 2.1
this is now the preferred build to use from the official Mixxx PPA source, so the previous posts about using specific alpha builds or building from source are obsolete.
The Download instructions, including Ubuntu Linux PPA install source, are here:
MIXXX Download Instructions
The ZOG DJ rig is still:
Pioneer DDJ SB2
Dell Latitude E6410 with i5 M540 CPU
It has been upgraded with a Toshiba OCZ TR150 Series 960GB SSD.
Xubuntu Linux, 16.04 -lowlatency kernel