My etrex 20 wont turn on with a Sandisk 8GB microSDHC card installed. Pull the card out and it works fine. Before purchasing a card, I called Garmin and asked what type of card they recomend. The techs response was- any card up to 16 GB, any manufacturer, as long as its NOT a HD card. I asked if the SDHC would be ok and he said yes, make sure its not high definition. Anyone else having a issue?