I would recommend going into the receiver settings to check the audio settings. Verify Secondary Audio Programming (SAP) is off. If it is off, then turn it on, then back off again. Exit the menu and check for the audio again. If not resolved, then verify the TV audio settings that it is off as well.
After these steps, if the audio is not normal, then I recommend unplug the receiver power for 20 seconds and allow the reset to finish. Please update us on your findings.