My ds600x was fogging up so I sent it in to Raymarine for repair. They sent it back saying they checked for moisture damage and there was none.They treated inside with antifog and added dessecants.I was under the impression that these were sealed units so I called and asked someone who was some kind of boss and they told me these aren't gas filled or sealed and that they would cost 20,000 dollers if they were.When I told him my Garmin gps that sits right next to it has never fogged he didn't say anything.<br />Has anyone experienced fogging with these units or had a similar experience?<br />I can't help but think I'm getting the runaround.<br /><br />Any advise or comments will be appreciated.<br />Thanks <br />Dan