Hello I am P2 diver and using my unit 3 years , last few dives I am facing with HUD shut off after approx. 30 minutes of dive , after pushing on ON button HUD is switched on for another 30 minutes . I am using SAFT AA , 3.6 V battery , battery checked and is still new , replaced HUD and problem is still existing . If somebody faced with the same problem , please share and comment .