We just spent a few weeks in Mexico where we do some shore diving. The three of us all have Oceanic Veo 250 computers in consoles. Mine is in an older rubber console and the other two are in the fancy molded console. I lost my compass so changed to a spare molded console. I discovered right away that the compass was not to be trusted. My wife never uses hers so she never noticed but I found the other guy with us was fighting his. In my rubber console the compass is not right next to the computer but in the molded console the compass is exactly opposite of the computer. When the compass is really close to the computer it doesn't work. Further testing revealed that the computer batteries were strongly magnetic and were the problem. I have placed an order for CR2450 non magnetic batteries. We will see