Here you go.
Description of issue:
Using Live TV in Windows Media Center to display the majority of my cable package's unencrypted HD channels produces a lot of visibly corrupt frames and audio glitches (the number of corrupt frames can be verified on the 411 debug menu). Not all of my HD channels have this issue -- some display with no corrupt frames. People have referred to this issue in the past as: checkerboard artifacts, block artifacts, glitches, stuttering, corrupt frames, etc.
Here's a screen capture of the issue (also attached):
I get these gray and black corruption artifacts, appearing from the bottom of the screen every second or two, along with other MPEG-2 pixelation artifacts and audio stuttering.
When plugging in the very same external tuner and testing the very same channels on a different computer, I don't have this problem; this is how I know that the problem isn't anything to do with the cable signal.
I also don't think this is a Microsoft problem, as the channels in question display just fine on Windows Media Center on the different PC/laptop.
Furthermore, the HD 4600 itself can render some HD channels just fine, so I just don't think it's an issue of it not being powerful enough.
To be sure, the problem *isn't* the 29.97/59.94 frame rate switching issue that has plagued people in the past -- all of the channels in my case are at 59.94. The problem *isn't* the dynamic contrast setting in the HD Graphics Control Panel -- I have that turned off. The problem *isn't* only with 1080i channels -- it also occurs on 720p channels.
I have the latest Intel drivers installed.
I have the latest BIOS update from Lenovo installed.
I originally had a hunch that the issue might only occur on HD channels when they contained *more* than two audio channels in the broadcast signal, however, NBC6 in Miami, for example, which has 6 channels, doesn't always produce these corrupt frames, but has done so at times. Some channels more consistently produce corrupt frames than others, and usually these are ones more than 2 audio channels in the broadcast stream, but this may very well be a coincidence.
Answers (N/A if not applicable)
Provide a detailed description of the issue AND 'does it fail every single time, or only sometimes?' If you can offer a % rate please do.
Brand and Model of the system.
Lenovo ThinkCentre M93p (10AB-000KUS)
Hybrid or switchable graphics system? ie Does it have AMD or NV graphics too?
Make and model of any Displays that are used to see the issue (see note2 below).
LFP = Local Flat Panel (Laptop panel)
EFP = External Flat Panel (Monitor you plug in)
How much memory [RAM] in the system (see note2 below).
Provide any other hardware needed to replicate the issue.
ie: Cables&brand, cable type [vga, hdmi, DP, etc], dock, dongles/adapters, etc
I’m using the following TV tuner, however, other people have experienced the issue with other tuners. My tuner is the Avertv Hybrid Volar Max USB TV Tuner (Kit for Windows, for Windows Media Center)
Hardware Stepping (see note1 below).
Operating System version (see note2 below).
VBIOS (video BIOS) version. This can be found in “information page” of CUI (right click on Desktop and select “Graphics Properties”.
Graphics Driver version; for both integrated Intel and 3rd party vendors (see note2 below).
SW/Apps version used to replicate the issue.
Single display, clone, or extended (see note2 below).
Display resolution & refresh rate setting of each display (see note2 below).
1920x1080, 59p Hz
AC or DC mode, i.e. is power cable plugged in or not?
How to repro
Please provide steps to replicate the issue. These steps are very crucial to finding the root cause and fix.
A screenshot to illustrate the issue is a huge plus. A video of the failure is even better! Attach to the post or provide the YouTube link.
1.) Watch various HD channels in Live TV in Windows Media Center until you find one that displays this frame corruption.
2.) Once you see the frame corruption, you can type 411, then hit Ctrl-D, and use the right arrow key to go all the way to the right debug menu, where the "corrupt frame count" and "frame corruption rate" data are listed.