Speakers went to really low volume even when its cranked. What happened?

Hello, You likely have a bad fuse for the power radio amplifier, or the system needs a reset. Hyundai, even on the new models, has had issues with the radios either not playing sound, playing sound too quietly, not displaying the screen, etc. Kia too. If your fuses are good, reset the radio by removing the fuses for several minutes, or removing the negative battery cable for several minutes.