"O. Sami Saydjari" wrote in message
...
I have a Garmin 340 panel and the installer put a music input jack for
it. So, I tried plugging my portable MP3 player output into the music
jack. At maximum volume on the MP3 player, the music was almost
completely inaudible. Does the signal need to be pre amplified in some
way, or did the installer mess something up?

Did he ground the connection?