WMP and MPC stopped to show .mkv files that contain H.264 video

Hi,

Few weeks ago I replaced my old K-lite codec (from year 2014) with new KLCP v 14.5.5 standard because the old one did not play .mkv files with H.265 video.
Now both WMP and MPC do play .mkv with HEVC H.265, but they stopped play .mkv with H.264
WMP shows green screen without picture, but plays sound.
MPC shows just black screen and does not play at all.
My old K-lite played .mkv with H.264 without problems.

I also have AVS video converter, which uses own codec and it still opens .mkv with H.264.
If I convert .mkv with H.264 into .mkv with MPEG4(DivX/Xvid), both WMP and MPC play video without problems.

I looked in the FAQ of your forum but found there only description of the problem with playing .avi with H.264.

I tried Codec Tweak Tool -> Fixes
- Detect and remove broken VFW/ACM
- Detect and remove broken DirectShow
- Re-register DirectShow
- Re-register DirectShow from KLCP
This did not solve the problem.

Could you pls. help ?
Thank you very much in advance!


OS : Windows 7 Professional (6.01.7601) (x64)
CPU name : Intel(R) Core(TM) i7-2640M CPU @ 2.80GHz
CPU speed : 2791 MHz (4t)
Memory : 8160 MB
Screen size: 1920x1080 (32bits) (60Hz), 1366x768 (32bits) (60Hz)
Video card : AMD Radeon HD 6450M
VendorID : 1002, DeviceID: 6760, SubSys: 00041179
Video mem: 1024 MB
Video driver: aticfx64.dll (Version 8.801.2.3000) (3-2-2011)
Audio device: Realtek High Definition Audio
VendorID : 10ec, DeviceID: 0269
Audio driver: RTKVHD64.sys (Version 6.0.1.6293) (1-18-2011)

These are examples of the videos that do not play:

VIDEO 1

Format : Matroska
Format version : Version 4
File size : 3.62 GiB
Duration : 1 h 45 min
Overall bit rate : 4 931 kb/s
Encoded date : UTC 2018-11-27 05:05:59
Writing application: mkvmerge v14.0.0 ('Flow') 64bit
Writing library : libebml v1.3.4 + libmatroska v1.4.5

Video
ID : 2
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 5 Ref Frames
Format settings, CABAC: Yes
Format settings, ReFrames: 5 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 1 h 45 min
Bit rate : 4 545 kb/s
Width : 1 920 pixels
Height : 800 pixels
Display aspect ratio: 2.40:1
Frame rate mode: Constant
Frame rate : 23.976 (23976/1000) FPS
Color space : YUV
Chroma subsampling: 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame): 0.123
Stream size : 3.34 GiB (92%)
Language : English
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.709
Transfer characteristics: BT.709
Matrix coefficients : BT.709


VIDEO 2

Format : Matroska
Format version : Version 4
File size : 3.41 GiB
Duration : 2 h 14 min
Overall bit rate : 3 625 kb/s
Encoded date : UTC 2018-09-23 06:42:52
Writing application: mkvmerge v26.0.0 ('In The Game') 64-bit
Writing library : libebml v1.3.6 + libmatroska v1.4.9
Cover : Yes
Attachments : Cover - Thumb.jpg / Cover.jpg

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 5 Ref Frames
Format settings, CABAC: Yes
Format settings, ReFrames: 5 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 2 h 14 min
Bit rate : 2 850 kb/s
Width : 1 920 pixels
Height : 800 pixels
Display aspect ratio: 2.40:1
Frame rate mode: Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling: 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame): 0.077
Stream size : 2.69 GiB (79%)
Writing library : x264 core 155 r2901 7d0ff22
Encoding settings: cabac=1 / ref=5 / deblock=1:-2:-1 / analyse=0x3:0x133 / me=umh / subme=10 / psy=1 / psy_rd=1.00:0.25 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-6 / threads=24 / lookahead_threads=4 / sliced_threads=0 / slices=4 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=1 / weightp=2 / keyint=240 / keyint_min=23 / scenecut=288 / intra_refresh=0 / rc_lookahead=60 / rc=2pass / mbtree=1 / bitrate=2850 / ratetol=1.0 / qcomp=0.60 / qpmin=3 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=62500 / vbv_bufsize=78125 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00
Language : English
Default : Yes
Forced : No

Disable hardware acceleration in the settings of LAV Video decoder.

A newer AMD driver may fix it, but I don't know if a newer one is available for your laptop.

Codec Tweak Tool - Configuration - Directshow Filters - LAV Video decoder
Hardware Acceleration - Harware Decoder to use = DXVA2(copy-back) -> None

The problem has been solved, Thank you !
Unfortunately I could not find newer AMD driver