I'm now using ZTE H618B with Tomato Pandora. RAM increased to 64M. I used a USB camera. In the much bright, much dark circumstance and some normal bright circumstance, the frame becomes abnormal. Why? So one said it's the problem of voltage. I measured that it's 4.95V, no matter USB camera is connected or not. So the voltage is in the normal range. In order to make the 5V much smooth, I jointed a 470uF capacity additionally. But problem still remain.