At the first hearing, you admit or deny the violation. If you admit it, the court may sentence you to any jail time and/or fines that would be normally stayed. If you deny - the court will set an evidentiary hearing to prove the violation. If you are found to have violated, again, the court may sentence you to any time previously stayed.
If you're set for a hearing, that means the probation officer (po) has already violated you. So, yes, it may be possible for you or your lawyer to speak with and convince the po to not violate you, and that would end the matter.
Once the po does violate you, you appear in court to admit or deny. The standard for a violation is that it must be a willful and substantial violation. Your lawyer can advise you on whether the facts are defensible. If you admit the violation or lose the hearing, you will be sentenced.
Sometimes, there is an offer from the state of what you will get for a violation, but of course that requires an agreement from the judge. Some judges will agree to most things but others consider the probation to be "theirs" and want to fashion their own punishment.
At the hearing itself you will either admit or deny. If deny, then you go to an evidentiary hearing, like a mini-trial but with far fewer protections for you. If you win, it's over. If you lose, the judge will sentence you, possibly adjudicating you of the original chage if previously withheld, and adding if he or she wishes to with anything that is within the allowable maximum sentence for that original charge.