I have a '07 Harley radio that i am not able to hear any sound through the speakers. When i turn on the radio, the screen comes on, volume control shows turning up and down and changing stations also but still have no sound at all. Is there something i can do or is this a "send in to get it fixed" deal? Are these radios repairable or is it time to look for another radio? Hopefully this radio can be repaired. Thanks for any of your help.