Happened to me once, also. Dot appeared to be moving low, across the deck. I'd dive down towards it, and then it would suddenly accelerate up and over me, and reappear low and on my six. After a few times of this, I decided, "HAHA - I'll film this and send it to HTC!". Brilliant idea, of course, but when I viewed the film, the dot wasn't able to be seen. It looked like I was just diving and zooming for the fun of it.
At the time I thought I'd had too many painkillers - nice to see someone else has seent he same thing!
