Today I purchased a Humminbird VHF 55 handheld marine radio. Checking it out I found that pressing any of the keys made a sound like most key devices but the sound the radio keys made is so loud it is annoying. I checked the manual, the radio volume control and the radio for an on/off switch but found no way to turn off this sound or soften it. I think the radio is OK but just don't care for this sound. Is there someone out there that has one of these radios that could tell me how to mute this sound or should I just return it and try another brand? Thanks.