----------- found the cause,- it was having anticipative and synchronous multiprocessing enabled. disabled those and now all is sweet even at 3ms,- dragging windows around like a loony and NO CRACKLES! haha - simple little thing but it feels like a new machine :) ---------- OK. Can anyone here have XP with the "show window contents whilst dragging" enabled and drag their reaper mixer around whilst playing back a reasonably busy mix and not get crackly audio at say 5ms audio latency? If you can,- did you get a new video card? did that help? I'd love to be able to do this without getting crackles but cant. I've got no IRQ sharing, PCI Latency timers have been tweaked either way to no avail.. I have an Nvidea 5200 FX video card which should be able to deal with this surely? Kind regards Dave Rich

also note: there are different reaper options for render priority. have a look at the "lazy update: always" option.

I honestly don't know how much the graphics card comes into play when moving system windows around.

I had an FX 5200 on my old Athlon based machine which suffered similar problems, upgraded the video card to a fast one with plenty of memory didn't change a single thing, nothing, nada. It did help with color reproduction thought, those 5200 were horrible with 2d colors and video, worst card I've ever used.

I've got a Q6600 quad core and a nvidia 8600GT (as mentioned above, the fastest I could find without a fan) No crackling here. Though not directly answering your question, I found the best way of dealing with space issues (so you don't have to do much window moving) is a second monitor. Most 8600GT's have duel heads. I can't imagine working without a 2nd monitor now.

bullshark,do you use a CRT or an LCD w/ analog input with the HD4850? I also find the analog output of the old 8500 to be far superior - the text is a lot more legible than the HD4850 at high resolutions (1600x1200,1920x1080 ,2048x1536) :)

I have an old pentium 4 3 Ghz (HT), 2 Go of DDR2, no graphic card (integrated intel chipset 915G), XP SP2, and have no crackling at all when moving the mixer around with the 'Making me nervous' project; if i double the amount of tracks, there's some light crackling when moving the mixer, and when alt-tabbing away.

I get noises if I run off the mobo's onboard sound. I can play a pretty mean tune just by moving the mouse cursor over the various firefox tabs ;D I would say you have a problem with any combination of mobo, audio card or graphics card.

How much of the rendering of any daw gets off-loaded to the gpu on the graphics card? I always wondered about that.

Dave, is the process priority set to 'background services'?