The back of my Garmin GPSmap76CSx tells a sorry tale.
Removing the waterproof plug for the UBS connector, to transfer a track to the computer, I noticed a green corrosion. Removing the larger external aerial plug, which I don't use, there was even more green corrosion.
This was registered on 7 May 2008. I look after my kit, keeping it in an Aquapack dry bag when just tracking a route and only leaving it exposed on deck to navigate with its maps. When home, the unit comes out of the Aquapack bag and dries in a warm room where it's stored.
So why the corrosion? And what will Garmin do to help? I e-mailed Monday night and they promise a reply within three days. Let's see.