I have had the R7 3 minths now and it I absolutely love it, however, las few times I have used it after a period of use it starts to shut itself down.  When it does this I turen it back on and as soon as it boots up it shuts down.  The first time this happended I reformatted the SD card and factory reset the device.  A few days ago it did this again and I stopped using it for about 15 minutes and then went back to it and alothough it booted up and stayed on it shut down after a few minutes.

Has anyone else had this issue?? Does anyone know what it could be?