I'm noticing the screen drawing is a bit slow (both X1 and X2). Just enough lag to be slightly annoying. Been like this for a year or so. No system change caused it - just gradually noticed. If I wave the mouse around a lot, the Task Manager shows 25% usage but Sonar CPU meters show nothing. I confess to running XP on an i5, Nvidia 9800GT graphics card. Used to be a top-line system, and still has no trouble recording/playing back projects at 4ms latency. Anyone have any ideas what might be causing this? I have a vague memory of an option to trade-off graphics drawing vs CPU for record/playback but can't find it. Cheers, Peter.

Since you're running an old 32-bit system, you're not getting full use of your 4GB of memory. 

True, but I don't think that's the problem. I noticed just now that it seems to be a single audio track with audio snap enabled that is causing the slowdown. If I change the track edit filter from Clips to Audio Transients, the problem goes away. Also, if I save the project that way, it's fine when opened. I can also delete all other tracks and save, and still have the problem. So probably not memory. Thanks for the suggestion though. Cheers, Peter.