[b]MediaPortal Version[/b]: Latest
[b]MediaPortal Skin[/b]: Default
[b]Windows Version[/b]: Windows 7 Ultimate x64
[b]CPU Type[/b]: Intel Core 2 Duo E7200 2.6 Ghz
[b]HDD[/b]: Seagate 750GB
[b]Memory[/b]: GSKILL 2X1GB DDR2-1066
[b]Motherboard[/b]: Asus P5K-PRO
[b]Video Card[/b]: XFX 9600GT 512
[b]Video Card Driver[/b]: v266.58 (Latest)
[b]Sound Card[/b]: Onboard
[b]Sound Card AC3[/b]: 1 x  Coaxial Out
[b]Sound Card Driver[/b]:
[b]1. TV Card[/b]: HAUPPAUGE HVR2200
[b]1. TV Card Type[/b]: Analog DVB-C, DVB-S, DVB-T
[b]1. TV Card Driver[/b]: Latest
[b]MPEG2 Video Codec[/b]:
[b]MPEG2 Audio Codec[/b]:
[b]h.264 Video Codec[/b]: AVC, Cyberlink, FFDSHOW (Trying SAF5)
[b]Satelite/CableTV Provider[/b]:
[b]HTPC Case[/b]:
[b]Cooling[/b]: Artic Freezer 7
[b]Power Supply[/b]: Silverstone 500 Watt
[b]Remote[/b]: MCE/Harmony One
[b]TV[/b]: Panasonic Plasma TH-42PY800 FullHD
[b]TV - HTPC Connection[/b]: DVI-HDMI

I recently decided to uninstall hd pack 2.6 and try SAF 5 unlocked version, I followed the [URL="http://forum.team-mediaportal.com/codecs-331/saf-v5-01-final-based-ffdshow-dxva-decoder-77591/"]Guide [/URL] but still having issues with playing mkv files with specs like;-
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format_Profile                   : High@L4.1
CodecID                          : V_MPEG4/ISO/AVC
BitRate/String                   : 10.2 Mbps
Width/String                     : 1 920 pixels
Height/String                    : 816 pixels
ID/String                        : 2
Format                           : DTS

Problems in particular are; delay in starting the playback, stuttering although (A/V is in sync), if i FFWD few min then audio starts playing but video catches up after few secs (3-4).

A thread with similar sort of problem says I should untick h264 from HWA menu in FDDShow - Config Video DXVA and try playing back the troublesome mkv's. I did this and they play fine, i mean not the smoothest motion but at least the symptoms described before are not present. I then reinstall the graphic card drivers and reticked the h264 option in Config Video DXVA but no change.

Attaching Graphstudio screenshot