Win7's Explorer Green progress bar is affecting my drive performance

I have a 1TB USB3 drive plugged into my router and it's shared NAS style to all machines on the network. On one machine I copy mostly large-ish video files (100MB -> 1GB) to the NAS drive (via regular explorer copy/move operations). Then on other machines I'll read those files.

What is happening is that I'll open an explorer window to my Z: drive which is permanently mapped to the NAS drive, and I'll see almost instantly the contents of the folder I've navigated to. Then, I'll see the green bar of doom scan, and it'll take about 5 seconds to complete. Then I might open a video file and play it in VLC and as I look back I see the green bar doing another scan. It seems to keep re-scanning for no apparent reason. The view mode of the explorer is set to "Details", so it shouldn't be trying to make any thumbnails.

The worst situation is if another machine is trying to copy files to the NAS drive when I happen to have left an explorer window open to that same folder on my main machine. The green progress bar/scan goes over and over and over, and if I look on the "copier" machine, I might see 40 minutes remaining to copy a simple 500MB of files. But if I close that open explorer on the main machine (that was doing the green bar scans), then I see that the copier machine is now showing 5 minutes remaining. The green bar is slowing down everything.

Is there a way I can disable that re-scanning? I've searched and can't find anything. I'm happy to have to manually refresh a folder which may have had its contents modified by another machine. I don't need this auto-refreshing which is killing the performance.

Can't believe that this has bugged me for a long time, and just posting this question here made me find the solution. Although I was in details mode, to avoid my codecs having to generate thumbnails, I actually had added the "Length" column to that detail mode. So the codecs were being called upon to find the length instead. It's still annoying that it would refresh so often, but now it's so quick that I don't even see it happening, now that it doesn't need to calculate lengths.