The facetious answer is, you can do anything. But the smart answer is, you should almost never, ever withhold support payments. The court takes a dim view of anyone who tries to leverage their parental obligations and paying child support is a parental obligation. Legally, child support is owed to the child, so if you withhold it, you are only hurting your child. The court naturally interprets these actions in a very negative light. Often withholding support can backfire and hurt your chances of modifying child custody.
The classic example occurs when your spouse interferes with or prevents you from seeing your child per the agreed child custody agreement. Naturally, if you regularly pay your support payments and always return your child on time, and if your spouse behaves poorly, you want to exert influence to modify the custody order. But you need to resist this urge.
It is far more efficient to request a modification of the visitation schedule and proceed through the judicial process than to try and force a change on your own.
Of course, the easiest solution is if you can work it out with your spouse on your own. If possible, you should try an informal resolution. For example, you may discover issues of which you were previously unaware. For example, perhaps your ex-spouse is dealing with an issue at work or a familial issue. Once you talk it over, you might be able to resolve the issue with a modified schedule that helps both of you.
If you do decide to proceed with the court, you may want to consult a family law attorney. The court always reviews any modification to child custody agreements in light of what is in the best interests of the child. A lawyer can help you organize the various events and present a coherent argument to the court.