O.K. so last night I renamed the AUD.INI. Rebooted and an new one was created. I found the DropoutMsec and it is defaulted to 250. I will change this to 500 if I get those white noise dropouts during playback or dropouts during recording. I changed my buffer to 512 in Motu. I changed my buffer to 512 in Sonar in the "Advanced" tab of the Audio Options panel in Sonar. I just searched for a screen shot of the panel so I could specifically tell you what, but could not find it. In any event there are two adjustments for this just at the top and I changed them both to 512. Still moving forward and will keep you updated, thanks all.

The change to 512 of the I/O Buffer Size in the "Advanced" tab is a big jump from the default of 64. It does not need to be set the same as the latency buffers. Might want to try 256 first. Always use factors of 2 for this setting i.e. 16, 32, 64, 128, 256 or 512.

  Good point. I don't know that I can say what the default is. I know when I looked at it, it was at 256.

  Here are my observations from this weekend. I updated my Motu drivers. I installed DPC Latency Checker. I disabled the wireless card, modem, internal sound card, Windows Defender, Microsoft Security Essentials. I have the power management set up for performance and can't shut it off. I would prefer to not have Windows monitor my power management, but can't seem to disable it. I opened Windows Explorer, Sonar and DPC. I observed DPC for an hour while rehearsing. Nothing was running on the PC, although Sonar and Windows Explorer were open. I had yellow and red spikes. The red never reached the top but did happen. When recording, I had no dropouts or stuttering, also no pops and clicks. Something is running in the background and I can't find it or figure it out, but I have to in order to get the pc running clean. I also noticed that if I grabbed a window and moved it around the screen it would create a red spike that went all the way to the top. Please let my know what you think, thanks.

I tried to get Sonar to run on a Sony laptop Dual Core, 2 Gigs RAM, running Vista. Could never find what caused the spikes. Sony was no help they had it for a week and said it was running perfectly. I disabled half the processes,wireless ( switch) lan, battery management , there was nothing in this computer, bare bones. Took a week to delete Sony Bloat ware etc. No Go. So I borrowed a Lenovo Think pad i5 6 Gigs RAM with W7 and the DPCLAT ran in the low greens ( 100ms) with no disabling anything, the wireless is even on. Vista defaults to over 70 processes running, It's a dog, See if you can upgrade to W7.

  I wish I could, but not without upgrading Sonar too. I mean really...I have to go to a complete upgrade to Sonar to use Windows 7 or 8. It sucks. Thanks man.

If you have "no dropouts or stuttering, also no pops and clicks", it sounds like you are in good shape. I do not believe you are supposed to be running anything while the DPC Checker is testing your system. If I were guessing why you spiked when moving a window while the DPC Checker was running, it is probably related to your video driver. There might be an update for it. But again, if you are recording OK, why mess with it.

  Good question. When I run DPC checker without any recording or playback activity and it spikes...to me this is an indication something is running. I think the dropouts or white noise during playback may be the combination of me taxing the system at just the same time that it is spiking because of something else that I have not found yet and that combined with me taxing it during recording or playback may be all it needs to dropout or stutter or fail in some way. When this occurs I "of course" get the dreaded message from DPC telling me my system will not work when streaming audio or video. So, for me, trying to get rid of the spikes all together will give me a more stable system. This week or weekend I hope to start mixing some songs again so I will surely tax the system greatly and the problem might rear it's ugly head again. I will let you know.

You might want to run LatencyMon http://www.resplendence.com/latencymon it may help you narrow in on what is causing the spike.

  Thanks Scook. I have it ready to go when I get in the studio. Knowing my luck, I would need to purchase the professional version for $119.99 in order to solve any issues...lol. It looks promising though, thanks again.