Parts "sticking" when manually placing in PCB Editor

Hello,

I am a new user of Cadence Allegro, though I have used other (lower-end) EDA software packages before.

I am running SPB16.01 under WinXP, and I am running into some unhelpful/annoying behavior when placing parts into my layout. Here is a quick summary of what happens:
I import a netlist from our designer (he is using Capture CIS & I use custom footprints for all parts) - this goes just fine now.
I click Place...Manually, check all components, and start placing them on the board. This is where things get annoying. Every new part that gets placed seems to be "sticking" to the most recently-placed part if there is a logical connection between the new part and any other already-placed part. What I mean by sticking is that i really have to jerk the mouse to get the new part to be in a new position in the design. If I move the mouse slowly, regardless of how far i move it, the new part will move a small bit and snap back to lying on top of the last part. If the new part has no connections yet (i.e., the other parts to which it has connections have not yet been placed), I don't see this behavior. It seems to be related to the redrawing of the rats nests, but I am not sure.

I have gone through the Setup...User Preferences menus about a dozen times and I cannot find anything that seems like it would change this behavior. If I "unrats all" after a component is placed, the components that are already placed stop "sticking", but each newly-placed component will stick. The design I am working on currently is a small project -

Any help on how to change this behavior would be greatly, greatly appreciated.

Thanks in advance,
-philip olson