I just noticed your post, too. I had the same problem with my DX200, only worse. The UI seemed to have a mind of its own, both in Android and Mango. At times it was unusable. It was very irritating. It seemed to me like it might be a hardware issue involving the touchscreen capacitors, but it's hard to say.
I've returned it to the vendor, who pledged to ship out a replacement. Hopefully, soon.
Did both of you guys who had UI issues buy your DX200 from Amazon U.S?
I have the same issue. Virtual taps and swipes on the screen. First day, just received from amazon us. This is very frustrating and makes the player unusable.