Screen "flickers" on some channels

[mikeh49]

After installing a HD5450 video card of a different brand, I now have flickering on some channels, with USA the best example. The flickering is a lightening-darkening of the overall picture at about a 2-3 Hz rate. I think I may have had this in the past, but I don't recall what fixed it, or if it went away. Here are the specifics:

Win 7 Home Premium
MS DTV-DVD video decoder
AC3 Filter audio decoder
EVR renderer
All others default
HD Homerun Prime tuner

I did not do anything to the video drivers; I just let Windows do its thing. The AMD driver is 12.x or something like that, checked in Device Manager.

The channel (USA) plays in HDHomerun View with no flicker. A recording from USA plays in VLC with no flicker. VLC says the file is 1080i.

In NPVR, live TV flickers as well as multiple recordings from the channel. I think PBS is 1080i, and it plays fine, as do all broadcast channels, so not all 1080i is affected.

I ran the latest NPVR installer to get all the updates; no difference.

The file plays fine over the network on my NPVR test box running an earlier install of 3.4.8.

The NPVR log is unremarkable, but I'll get if needed.

Contrary to the signature, I'm running 3.4.8.

[sub]

It's gotta be either the video decoder or video renderer, since these are the items that makes the video frames and display them.

[2leftfeet]

I use an HD5450 in 4 different PC's without problems in NPVR or other app's as well. Make sure you are using the latest
ATI drivers.

[mikeh49]

Found the solution: uncheck Enable Dynamic Contrast in Catalyst.

Lesson to be learned - check all video settings in a working system before changing video card.