Just FYI: I've investigated this issue last week and spent quite some time on it. I can reproduce it but unfortunately, I couldn't find any cause for this.
I've even developed a small example program and asked for help at Stackoverflow, but so far nobody was able to reproduce it. Here is the link in case someone wants to jump in:
https://stackoverflow.com/questions/4450713...scroll-position
Kind regards
– Florian