Refresh after changing FX settings

[djm99001]

Hello all!
I'm running TVP (non-pro) 8.5.9 on two computers--a tabletPC and a desktop, both WinXP (home on desktop, pro on laptop).
I am moving some shapes around with the keyframer, and when I make changes to a property (say, the X Position), the change updates as soon as it renders on the laptop, but on the desktop it doesn't update until I touch the playhead.
At first I thought it was a simple interface thing, as if I wasn't keeping the window in focus or something. I remember, that as of 8.5 I have needed to touch the tablet surface while pressing the sideswitch on the Wacom, and I seem to remember this problem surfacing on the desktop at that update. I didn't have the problem in versions before that. But the laptop doesn't exhibit this, and the only difference is the pointing device. Both Wacom, though ("penabled" and Intuos3).
Any ideas?

Thanks in advance!
David

[Hervé]

I can't reproduce that behavior David.
What is your wacom driver version ?

[djm99001]

I am using Wacom Control Panel (and driver) Version 6.05-7.

Here is another important observation. The HUD updates in realtime when I change the position, but the new, updated image does not redraw until I click the playhead (or uncheck and recheck "preview"). It's like the image makes no attempt to keep up with the HUD.

Thank you,
David