Many engineers use a limiter plug-in to raise the overall level of final mixes when mastering. The problem is that pushing the limiter too far will result in audible artifacts. (Why we push the limiter too far is another discussion entirely…)
If this happens, try using two instances of the plug-in in series (one before the other), each raising the level moderately. This way, neither limiter is being pushed as hard, and often, cleaner results can be achieved for similar level increases.