Philips 32PW9617 question

Hi

Several months ago I purchased a Philips 32PW9617 and was pleased with its performance until I noticed a problem with the pixel plus scanning mode. I am aware of the shimmering effect on fast camera pans, this is not the main problem though. The problem is that on fast motion scenes I am aware of visible line structure running across the fast motion on the screen. Is this normal or have I a problem with the scanning mode of Pixel Plus. This problem does not occur on double line mode or 100hz mode.

Would appreciate any comments to the above question.
Thanks for looking
Shaun