It takes two buttons to get into your Nitrox Set (F) mode. If you don't SET the mode, it will always default to gauge mode until you disallow access using the desktop computer program you can download for free on Aeris website.
The ai's we have had some battery compartment problems, which were all repaired under warranty. Before you "look for a real computer," make sure your computer isn't too smart for you.
Next time use a table if you don't know how to use your gear.
Just because it's high dollar doesn't mean you don't have to think.
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