I have no idea whether the two Suunto Zoop computers we own are defective, or whether the audible alarm is too weak to hear when you have a hood on. The computer is supposed to alert you when you go into deco time, and also when ascent rate is exceeded. Admittedly I've never heard anything underwater after 4 years of use. I purposely went into deco last week while watching the computer, the gauge was a foot from my ears, and I heard nothing, no hint of a sound. My wife has had the exact same experience recently. The battery has lot's of capacity remaining, and water temperature was 13 degrees celsius. The gauges like the rest of my equipment have always been properly cared for. Albeit I'm not advocating you ignore visual readouts, the audible alarm is quite useful as a photographer, who can often can be distracted by their subject and lose track of time. I got caught out recently, and fortunately had plenty of air remaining to fulfill the 16 minutes of deco time I'd racked up. Needless to say I would've made a more informed decision had I of heard the alarm, instead I was forced to be reactive.

I'll be speaking with Suunto at the dive show in Birmingham, as I personally I think this is dangerous. Having used an Aladdin Pro for years which was flawless and the audible alarm more than adequate, I find this major cause for concern. We all trust our computers to work as designed, and our life as diver's depend on gauges working as designed. Look forward to hearing from anyone else who's experienced similar issues.