These students may not be doing anything outrageously bad, but their behavior is still disrupting learning. These are the kinds of things that can be really frustrating for a teacher.
A lot of times the students who push the limits without quite crossing them are the upper level, honors types.
I am a fan of keeping track of cumulative misbehavior. If a student crosses a minor boundary once or twice it may not be a big deal. It is when students cross the same boundaries over and over again that problems can occur.
The best way to prevent regular but minor misbehavior is to keep a record of it. When the number of infractions becomes too high, a consequence may be in order.
Set limits and stick to them.