I've been suffering from periodic audio stutter while using Vista 32bit and Live 7.0.14 for quite some time now.
So the problem I had was that every 2-4 seconds the sound stopped while in session/arrangement view.
It drove me nuts and at some point I decided to check it as much as I could.
So I found out about the DPC Latency checker & the XPERF tools from microsoft (you download an MSI file and install).
The DPC latency checker did indeed confirm that there was a periodic issue below 1000us but coincided well with the stutter in Live. However this tool doesn't tell you anything about the source/origin of the issue.
Opening task manager right after boot (and without opening live & network disconnected) revealed that a system process occupied 4-5 % CPU.
This is when the Xperf tool came in handy...
The idea is that you run it on a command prompt as an administrator.
In turn you switch it on, stop it , and launch the interactive viewer
C:\Users\xxx>xperf -on DiagEasy --> this starts it
C:\Users\xxx>xperf -d trace.etl --> this creates the log file & stops it
Merged Etl: trace.etl
C:\Users\xxx>xperf trace.etl --> this launches the viewer
Well, in the UI's left column you can choose what you want to see
Intentionally I had run this tool while the computer was idle, for a period of 1.5 minute or so. So nothing opened, except the command prompt launching the tool.
The CPU usage graph indeed revealed periodic peaks. You can use your mouse to select the start-end time you want to be further analysed. so you drag an area and then you right click and select "summary table".
That revealed the culprit: Selecting the system process, and further expanding it to see what was the highest consumer, the Xperf indicated that the iaStor.sys was 82.192429 ms amounting to 2.48% CPU usage.
It doesn't sound much but if that system process has high priority, you get the idea.
Searching for this problem didn't help that much. Until I went to intel's site...
http://www.intel.com/support/chipsets/i ... 025783.htm
Installed the suggested iata87enu.exe and no more drop outs!he following issues may occur on Windows Vista* with a supported Intel® RAID controller hub:
* Inability to install Windows Vista (in other words, system halts during installation)
* Performance degradation
* Timeout errors reported by iastor or iastor(v) in Microsoft Event Viewer*
Please note that during this process I've disabled everything there's to disable in Vista. But this in my case helped. If you do suffer from this issue, its really worth downloading the Xperf tool and see what's keeping your system from performing. I couldn't believe for a second that a Core 2 Duo 1.8 with 3Gb of ram could have such performance issues. But the OS is part of the problem. Driver developers are the other. Thats only human.
I hope someone resolves their issues with this too.
greetings!
