Relentless touring and high-profile promotion, like giving DJ lessons to Miss October, hasn’t loosened A-Trak’s lock on the hipster-approved party mix. Pivoting away from the exemplary fusion of hip-hop and dance achieved on Dirty South Dance, the Fool’s Gold godfather delivers an energetic shuffle of quick changes and churning club beats on Infinity+1. The standard cast all make cameos, from DJ Mehdi (“Pocket Piano”) to the plucky Kid Sister (“Life on TV”) and beardy playboy Sebastien Tellier (“Kilometer”), but a few glittering disco-infused tunes provide a bit of variety. A-Trak maintains a relentless pace, but this is not his finest mix. However, it’s fun and flashy, which is what he does best.