PP crashing while working in Sequence [\TrackItemTrack.cpp-639]

Question

Hi,
first Post, I'll try to do well in first attempt.
PP 5.5 is crashing with this Debug Event PopUp
[..\Src\Sequence\TrackItemTrack.cpp-639]
let's me "continue" and then it is broken.
This happens I think randomly soon after I start working with the project. Once it happened right when I right-clicked on a clip in the sequence, but it also happens while watching a tape.
First it was either this or an slightly different error, I tried to fix by removing some .jpg images from the library and the cache folder which made the error to occur "later" after opening the project again.
Now, I tried to disable - enable my sequence content and to import the sequence from another copy of the project.
PP5.5
Windows 7 64-bit
PP on Windows SSD (120 gb)
1440*1080 HD Material on 1tb HDD
Radeon HD 4870 with 11.10 driver
Speedfan shows normal temperatures Procces Explorer shows http://imgur.com/MH10T
PP Screenshot http://imgur.com/rHhFW
Edit: Also, when I want to add clips from Source Monitor, they seem at normal size when moving over the sequence and seem shortened when placing them. And this happens also http://www.youtube.com/watch?v=XCZ0nsU6c88

Answer 1

Congrats on a nicely documented first post. The only thing missing is a screenshot of the error message itself and when exactly it happens and where on the timeline when playing, so we may be able to reproduce that error.
Your Process Explorer screenshots are very nice to see. Your system with only two disks and stuck in software MPE mode, due to the Radeon card, can use all the help it can get to make for comfortable editing. From that perspective you should really tune your system. See this link that also applies to Win7: Adobe Forums: Guide for installing and tuning a Vista...
From a quick look at all the processes running, I assume you still have the sidebar installed. If so, completely uninstall it from Control Panel. Kill all the Apple processes like iTunes, iPod, mDNSResponder. Do the same for all the G Data anti virus and firewall processes, kill all the unnecessary Logitech utilities and possibly the Acronis imaging software. That will free a lot of resources, making for a snappier editing experience. Last, don't run Chrome when editing.