Any warranty time left?
If not I would first go to Vizio's website and check their FAQ's and Forums.
https/support.vizio.com
See what you can learn. Then send an email describing the problem and see how they respond.
In the meantime google your specific model number and see if there are any widespread reports of problems (identical or not) with your model.
You can go to a repair shop but find out how much they will charge first. Some shops charge for repair estimates/assessments but may remove that charge if you actually have the set repaired by them.
Repairs are often guaranteed for only 30 days and something else entirely different could fail along the way.
Becomes a matter of the repair cost versus buying a new set that will have some warranty again.