[walltech]

I have experienced the same difficulty and was going to return it. Removed the SD card and cleared the memory. For various reasons, I decided to give it another try. Synced it, put the SD card back in and reinstalled the 3rd party programs I had on it before. Do not know why, but it has worked flawlessly now for 1 week. No more lock up problems. I do not mean to say that this is the answer, but it might give some insight to those who know more about these issues. Ill report back in another week.