Thanks for the reply one guy, have been on the phone all afternoon to fellow detectorists, sdc owners, gpx operators & Z men alike.Getting mixed replys.Mate was out on last trip & he has 4500 gpx , he saw my sdc flipping out day after day & he agreed that my machine was almost totally unusable, punctuated by suitable colorful language.Another mate has sdc2300 & gpz 7000, he has told me about the same random performance although nowhere near as profound as my experience.He went to tibboburra detecting in a group & there were 3 sdc's in the group , one of which totally spacked out for the whole time.Other sdc detectors working fine but one bloke (not me) had to sit back & watch everyone else pull nuggets.The sister of another prospector mate has the sdc 2300 as well & he saw that detector spacking out as well.She was furious & apparently tore the supplier a "new one' over the phone & was hell bent on getting a full refund.Another bloke she knows also has sdc & "fixed" the problem with a thin wrap of electrical tape around the batteries.Apparently the battery is not disconecting the power supply enough to initiate a2 resart of the detector but apparently the bad conection is preventing the detector from setting itself properly.Will try this tommorow & see if it fixes the problem.Either way, on face value, the problems i have heard of do not go hand in hand with a $ 4000 detector.I have stayed close to the goldfeild tonight & will try 2 salvage my sanity 2morrow with another effort.Either way i am definitely returning the machine for a refund, the product is absolutely defective & unacceptable. I feel like i have been ripped off.Just saying.