I have a Eagle Fish Mark 320. It's about 2 yrs old. I just was bragging last week how good it was and no problems with it??? I fished Saturday and it started out working fine and after a few minutes it just went to reading 0.0 flashing and showing nothing. I've had this happen one other time but I just turned it off and then back on and it started working fine however I couldn't get it to work Sat. Anyone have any ideas what maybe wrong???