Hyundai Repair Questions? Ask a Mechanic for Answers ASAP
Unhook the battery's negative cable. Leave it unhooked for a few minutes and play with the buttons on the radio while it is unhooked. Then hook the battery back up and see if the audio is back. This usually works. If that does not work, it's likely that you'll need a new audio unit or possibly an amp, both will be covered under warranty.
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