Led Lenser and Exped Gear Fail on trip

Hi guys, two probs, thanks for any help.
1.P7 Led Lenser, last week wouldn't turn off fully, always had a faint beam coming from the bulb. Also would not turn on with battery cap fully screwed in place, I needed to loosen it and jiggle it to activate the beam. Discovered there was a lump of grey dust/corrosion stuck on the inside of the metal housing, and grey dust all over the batteries and contacts. Funnily they were only a couple months old and torch had not been used much. I cleaned all of it off and replaced batteries but problem persists. Obviously I have beggared something in it? Its a heavy torch anyway I could always use this as an excuse to get a lighter one, however would still like it working to sell it off at least.
2. Exped SIM Lite 3.8 CM 2010 model, bought from a retailer last week. First week out with it and 2nd day sleeping it deflated, will not stay inflated more than half an hour or so. I left it in direct outback sunlight for almost a day accidentally( tarp blew down in wind) whilst I was out fossicking. Not sure if this could have effected it? Have tried the old tire tube method in the tub, cannot find any airbubbles. Valve also looks fine and closes properly. Retailer said it can only be one or the other and that these mats are checked at the factory by being blown up for 72 hours. However if this is a 2010 model clearance was it checked at the factory 5 years ago? Thanks for any suggestions.
1.P7 Led Lenser, last week wouldn't turn off fully, always had a faint beam coming from the bulb. Also would not turn on with battery cap fully screwed in place, I needed to loosen it and jiggle it to activate the beam. Discovered there was a lump of grey dust/corrosion stuck on the inside of the metal housing, and grey dust all over the batteries and contacts. Funnily they were only a couple months old and torch had not been used much. I cleaned all of it off and replaced batteries but problem persists. Obviously I have beggared something in it? Its a heavy torch anyway I could always use this as an excuse to get a lighter one, however would still like it working to sell it off at least.
2. Exped SIM Lite 3.8 CM 2010 model, bought from a retailer last week. First week out with it and 2nd day sleeping it deflated, will not stay inflated more than half an hour or so. I left it in direct outback sunlight for almost a day accidentally( tarp blew down in wind) whilst I was out fossicking. Not sure if this could have effected it? Have tried the old tire tube method in the tub, cannot find any airbubbles. Valve also looks fine and closes properly. Retailer said it can only be one or the other and that these mats are checked at the factory by being blown up for 72 hours. However if this is a 2010 model clearance was it checked at the factory 5 years ago? Thanks for any suggestions.