I also recently had an R-05 fail completely. Was recording all day long and in the 8 or 9th hour of recording, it locked up solid and then after taking the batteries out and messing around with it, it won't even power on. It wasn't a hot day and the recorder was sitting inside my bag. It had less than 40 hours of recording time on it. I'm pretty sure it would still be under warranty, but I never registered it and I don't have the original sales receipt anymore. Oh well. I bought an M10 to replace it.